ELECTRICAL POWERCH 24 STUDENT LEARNING OBJECTIVES: Upon completion, the student will be able to demonstrate an understand- ing of this ATA section by receiving a 80% or higher score on a comprehensive examination, meeting ATA Specification 104 Level III criteria. The student will: Describe normal and abnormal operation of the Electrical Power System Describe normal and abnormal operation of the Emergency Power Network Describe the operation of the Variable Frequency Drive Understand Electrical Power Distribution System Troubleshooting Identify potential safety hazards associated with the Electrical System and how to avoid injury or damage to equipment A350-900 ATA 24 TRAINING MANUAL PAGE - 1 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY A350-900 ATA 24 TRAINING MANUAL PAGE - 2 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY TABLE OF CONTENTS: AC NORMAL GENERATION - OVERVIEW ............................................ 4 EXTERNAL POWER ............................................................................... 6 EXTERNAL POWER MANAGEMENT ..................................................... 8 AUTO TRANSFORMER UNITS (ATU) - GPU CONFIGURATION ........ 10 AUTO TRANSFORMER UNITS (ATU) - VFG/APU GENCONFIG ........ 12 APU GENERATION ................................................................................ 14 VARIABLE FREQUENCY GENERATOR - INTRODUCTION ................ 16 VFG MANAGEMENT .............................................................................. 18 VFG OIL LUBRICATION AND COOLING .............................................. 20 VFG OIL SYSTEM MONITORING ......................................................... 22 VFG OIL SERVICING ............................................................................. 24 VFG DISCONNECTION ......................................................................... 26 DC NORMAL GENERATION - OVERVIEW........................................... 28 TRANSFORMER RECTIFIER - FUNCTIONAL DESCRIPTION ............ 30 MAIN BATTERIES .................................................................................. 32 MAIN BATTERY DESCRIPTION............................................................ 34 AC AND DC EMERGENCY GENERATION ........................................... 36 RAM AIR TURBINE DEPLOYMENT AND GENERATOR HEATING .... 38 RAM AIR TURBINE STOWAGE COMPONENTS.................................. 40 RAM AIR TURBINE STOWAGE ............................................................ 42 RAM AIR TURBINE GENERATOR MANAGEMENT ............................ 44 STATIC INVERTER AND EMERGENCY ATU....................................... 46 DC EMERGENCY GENERATION TR - INTRODUCTION ..................... 48 EMERGENCY BATTERIES - FUNCTIONAL DESCRIPTION ............... 50 EMERGENCY BATTERIES ................................................................... 52 DISTRIBUTION AC AND DC - COMPONENT LOCATION ................... 54 ELECTRICAL POWER DISTRIBUTION SYSTEM ARCHITECTURE ... 56 ELECTRICAL POWER DISTRIBUTION CENTER ARCHITECTURE ... 58 ELECTRICAL POWER DISTRIBUTION CENTER FUNCTIONS .......... 60 CIRCUIT BREAKER PANEL ARCHITECTURE ..................................... 62 SECONDARY POWER DISTRIBUTION BOXES .................................. 64 GROUND SERVICE CONFIGURATION ................................................ 66 TOWING ON BATTERY CONFIGURATION .......................................... 68 POWER DISTRIBUTION MAINTENANCE INTERFACE ....................... 70 PDMI ON BATTERY ............................................................................... 72 ELECTRICAL STRUCTURE NETWORK ............................................... 82 STUDENT NOTES: A350-900 ATA 24 TRAINING MANUAL PAGE - 3 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY located in avionics bay (pressurized area). The 28VDC network is composed of 2 main normal bus bars DC1-100PN. AC2A-200XPA. Transformer Rectifier Unit (TRU). TRU main electrical power source is available. Emer Hot Bus. and one OSFC). main emergency bus bars AC EMER1-300XH. one ASFC. DC F/ CTL. DC EVAC. The external power connectors are foolproof to avoid incorrect plug-in. The EP panel consists of a panel including two external power receptacles and The 230VAC network is composed of 4 main normal bus bars. indication lights (one “AVAIL” and “NOT IN USE” lights per external power AC1A-100XNA. In this scope. Also part of the engine system (one channel of EEC of each Two emergency batteries (BAT EMER 1 and BAT EMER 2) connected engine. and 2 main emergency bus bars DC EMER1-300PH. DC emergency network (391XD/INV AC1 from emergency battery 1 in several EMER2-400PH. DC NORM/BAT. typically during RAT deployment (around The DC generation consists of four identical and interchangeable 5sec). for ground phases (typically PDMI BAT1 on 100PN and BAT2 on 200PN on batteries). AC2A-200XNA. Each TRU is supplied with three phase In “normal configuration” on ground during aircraft power on when no 230 VAC current from the associated AC distribution network. In “PDMI on batteries configuration” on ground when no main electrical Two Transformer Rectifier Unit (TRU 1 and TRU 2) for the DC main power source is available. External Power Generation Two external power units can be connected to EP panel (located close to . AC1B-100XNB. transforms 28VDC Network 28VDC from emergency batteries into 1-phase 115VAC (fixed 400Hz) output supply. and when PDMI on battery mode is generation requested (maintenance purpose) Two TRU-EMER (1 and 2) for the DC emergency generation Four identical and interchangeable batteries (Ni-Cd) Equipment supplied by 391XD/INV AC1 include part of FSA-NG system Two main batteries (BAT-1 and BAT-2) connected to main DC busbars: (one SCI. DC SHED/GS. The 115VAC network is composed of 4 main normal bus bars AC1A- 100XPA. The power connector pins are directly connected to the concerned EPDC 115VAC Network via power supply feeders. to to emergency DC busbars: BAT-EMER 1 to the EMER DC1 – 300PH allow engine relight in case of electrical emergency configuration / Total and BAT-EMER 2 to the EMER DC2 – 400PH Engine Flame Out. AC EMER2-400XD. AC1B-100XPB. AC2B-200XNB. and 2 main Static Inverter emergency bus bars AC EMER1-300XD.4 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL SYSTEM OVERVIEW 230VAC Network the nose landing gear) to allow aircraft electrical power supply. and RAT not available. Static inverter. and when emergency transforms the AC into not regulated DC output by: batteries pushbutton are selected ON. AC EMER2-400XH. and 2 channel). DC PDMI. AC2B-200XPB. static inverter is used to supply part of the 115VAC DC2-200PN. and one channel of engine ignition system of each engine). The 28VDC network is also composed of several DC sub specific cases: bus bars: Hot Bus. when RAT is not available.A350-900 ATA 24 TRAINING MANUAL PAGE . In electrical emergency configuration (normal electrical sources loss). 5 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . ELECTRICAL SYSTEM OVERVIEW A350-900 ATA 24 TRAINING MANUAL PAGE . 28 VDC essential network through TR-EMER.6 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL SYSTEM OVERVIEW CONTINUED AC Emergency Electric Power The AC emergency electric power is extracted from air stream by a Ram Air Turbine (RAT) system. The RAT powers the AC essential busbars in the following events: Total engine flame-out (TEFO) which leads to total loss of hydraulic and electric power or. testing purposes and for maintenance testing. Slat electric motor. the RAT will provide 230 VAC power. Exceptionally. it could also be used in flight for training. at least. The main function of EMER ATU is to convert 230VAC 3-phases into 115VAC 3-phases power to supply the emergency network.A350-900 ATA 24 TRAINING MANUAL PAGE . the following consumers: Primary Flight Control Electro-hydraulic Actuators (EHA & EBHAs) on the three A/C control axis. Auto Transformer Units (ATU) Six ATU are installed on the A350: 4 main ATU for the normal network (ATU-1A. Loss of the Main Electrical System (LMES). Fuel electric pumps. ATU-2B) and 2 EMER ATU for the emergency network (ATU-EMER1. When one of the above-mentioned events is declared. . Miscellaneous loads. which is a stand-by system. It is inactive during normal flight operation and it is only activated when an emergency is declared. ATU-1B. ATU-2A. ATU are located in the avionic bay. Main ATU could also convert 115VAC 3-phases into 230VAC 3-phases power (when network is supplied by the external power unit). The main function of main ATU is to convert 230VAC 3-phases into 115VAC 3-phases power (when network is supplied by the VFG). ATU-EMER2). 7 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . ELECTRICAL SYSTEM OVERVIEW CONTINUED A350-900 ATA 24 TRAINING MANUAL PAGE . each external power unit can supply part or the entire electrical network on ground. and EP2 supplies the side 2 When connected. The Electrical Power Distribution Centers (EPDCs) monitor the GPUs and control the External Power Line Contactors (EPLCs). it can supply all of the aircraft electrical network but the automatic shedding inhibits some commercial (cabin) loads. If only one GPU is used.A350-900 ATA 24 TRAINING MANUAL PAGE . EP1 supplies the side 1. it supplies the side 1 and the side 2 When EP2 is available. the external power units enable to supply the entire electrical network: By three-phases 115VAC 400Hz constant frequency directly from external power units By three-phases 230VAC 400Hz constant frequency from 115VAC bus bars through ATU By 28VDC from 230VAC bus bars through TR . Basically. it supplies the side 1and the side 2 When EP1 and EP2 are available. depending on the electrical network configuration and electrical sources availability: When EP1 is available. The minimum rating of each GPU must be 90 kVA.8 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY EXTERNAL POWER General Description Two External Power Receptacles (EXT PWR RCPTs) are available to connect one or two 115VAC 400Hz three-phases GPUs and to supply the aircraft electrical network on ground. The GPUs can supply all of the aircraft electrical network through the transfer circuit. EXTERNAL POWER A350-900 ATA 24 TRAINING MANUAL PAGE .9 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . case of A/C shut down). Two redundant ENMU are External Power Disconnection implemented per EPDC. which sets the “power ready” signals to false. after having performed a safe vote. electrical sources statuses) allow it. contactor depending on electrical network parameters statuses (contactors statuses. and “AVAIL” light (located on the ICP). using the ICP “EXT” pushbutton (e.A350-900 ATA 24 TRAINING MANUAL PAGE . One EPCU is implemented per EPDC. and if network and disconnection of its associated external power unit (EPDC1(2) parameters (contactors statuses. Each Electrical Power Distribution Center (EPDC) manages the connection Each ENMU receives the “power ready” signals from EPCU. the External Power Connection ENMUs give priority to these sources and then command the opening of the EPLC contactor (through the EPLC CCM) Once an EP is connected on the EP receptacle. Then ENMUs command The External Power Control Unit (EPCU) the opening of EPLC contactor (through the EPLC CCM) EP disconnected in case of electrical power delivered by EP is out of The EPCU manages the EP and ensure the electrical network protection the required performance (in term of voltage. and frequency).10 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY EXTERNAL POWER MANAGEMENT signals to each ENMU (meaning that the EP electrical characteristics are External Power Management correct and crew wants to connect the EP). receives scenarios: commands from both ENMU DP. and the EPCU commands to OFF the The Electrical Network Management Unit (ENMU) illumination of “NOT IN USE” light (located on the EP panel) and “AVAIL” light (located on the ICP). and performs a safe vote to command ON/OFF the EPLC contactor. When the EP connection is required by the cockpit crew (through the associated ICP “EXT” pushbutton). and EPLC contactor command. The EPLC CCM. depending on electrical characteristics (voltage/frequency/current) of The EPCU sets the “power ready” signals to false. in (on EPLC CCM per EPDC). the “EP ON command” signal is sent from the ICP to the EPCU. Module (EPLC CCM). current. and commands to ON the illumination of “ON” The ENMU DP implemented in ENMU manages the external power line light (located on the ICP). the EPCU commands the illumination of “NOT IN USE” light (located on the EP panel).g. Then. The EP switch off order is then sent to EPCU. each manages EP1(2) connection/disconnection) and ensures the electrical ENMU sends the EPLC ON command to the EPLC Contactor Control network protection. command the opening of EPLC contactor (through the EPLC CCM) In case of higher priority source (APU. and if voltage/frequency/ current characteristics of the EP are correct. The EPLC contactor is closed. Each EP can be connected to electrical network through EPLC contactor. Each external power can be disconnected in the following three main The Contactor Control Module (CCM) implemented in ENMU. Then ENMUs power delivered by the EP. One CCM is installed per EPLC contactor EP disconnected by the crew. the EPCU provides the “power ready” . physically commands Two main functions/units hosted in EPDC are involved in EP management the closure of EPLC contactor. VFG) availability/connection. electrical sources statuses). “AVAIL” light (located on the EP panel). 11 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . EXTERNAL POWER MANAGEMENT A350-900 ATA 24 TRAINING MANUAL PAGE . 12 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY AUTO TRANSFORMER UNITS (ATU) . ATUPU sends discrete signal to ENMU and ATU is disconnected by opening ATUC and ATULC contactors. There are four identical and interchangeable main ATUs. For this function. The main function of main ATU is to convert 230VAC 3-phases into 115VAC 3-phases power (when network is supplied by the VFG).GPU CONFIGURATION the ATU. ATUPU received for each ATU a discrete signal “overtemperature” and analogue current General Description measurements signals. Nominal power of normal ATU is as followes: Power 60 kVA Frequency range from 360Hz to 800Hz (the output frequency remains the same as the input frequency) GPU Generation Configuration In the ground configuration. when the GPUs supply the aircraft electrical network: The 115VAC busbar AC 1A supplies the ATU1A The 115VAC busbar AC 1B supplies the ATU1B The 115VAC busbar AC 2B supplies the ATU2B The 115VAC busbar AC 2A supplies the ATU2A The ATUs supply 230VAC voltage: The ATU1A supplies the 230VAC busbar AC 1A The ATU1B supplies the 230VAC busbar AC 1B The ATU2B supplies the 230VAC busbar AC 2B The ATU2A supplies the 230VAC busbar AC 2A ATU Management The ATUPU (EPDC) ensures normal ATU protection depending on electrical characteristics (voltage/frequency/current) of power delivered by . and ATU monitoring. In case of failure.A350-900 ATA 24 TRAINING MANUAL PAGE . Main ATU could also convert 115VAC 3-phases into 230VAC 3-phases power (when network is supplied by the external power unit). GPU CONFIGURATION A350-900 ATA 24 TRAINING MANUAL PAGE . AUTO TRANSFORMER UNITS (ATU) .13 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . A350-900 ATA 24 TRAINING MANUAL PAGE .VFG/APU GEN CONFIGURATION VFG/APU GEN Generation Configuration In normal configuration.14 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY AUTO TRANSFORMER UNITS (ATU) . when the VFGs or the APU generator supply the aircraft electrical network: The 230VAC busbar AC 1A supplies the ATU1A The 230VAC busbar AC 1B supplies the ATU1B The 230VAC busbar AC 2B supplies the ATU2B The 230VAC busbar AC 2A supplies the ATU2A The ATUs supply 115VAC voltage: The ATU1A supplies the 115VAC busbar AC 1A The ATU1B supplies the 115VAC busbar AC 1B The ATU2B supplies the 115VAC busbar AC 2B The ATU2A supplies the 115VAC busbar AC 2A . VFG/APU GEN CONFIGURATION A350-900 ATA 24 TRAINING MANUAL PAGE .15 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . AUTO TRANSFORMER UNITS (ATU) . the SG supplies power to the aircraft electrical network when the APU is available. The SGCU has an ARINC 429 interface with the AFDX network through When the electrical parameters are correct. . A Permanent Magnet The SGCU has the protection functions that follow: Generator (PMG). Transformers (CTs) and the POR. The voltage regulation is The SGCU has an ARINC 429 interface with the ELMF that is hosted in done by adjustment of the current supplied to the exciter generator. an exciter generator and a main generator Over/under voltage The Starter Generator provides a nominal maximum continuous power of Over/under frequency 150 kVA on the ground. A detailed description of the SG is given in the related ATA 49 chapter. two CPIOMs.A350-900 ATA 24 TRAINING MANUAL PAGE . the SGCU supplies 28VDC energizing mode to the CDS. The ELMF gives overload protection by automatic according to current and voltage values sensed by the Current commercial-load shedding. has two functions: The APU is equipped with a Starter Generator (SG). The SG is a part of the APU system. Then.16 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY APU GENERATION General Description The APU GEN P/BSW. The Electronic Control Box (ECB) of the APU to receive APU ready signal ENMF has full authority over the connection/disconnection by sending this (N>95%) data. network Reset of the SGCU protection function In the Generate mode (auxiliary generation). for the SG Generate mode. 100 kVA in flight. ground/open signal. The SGCU has a CAN interface with the The ENMU provides the ground and together. The manual control of the SG is done through the SGCU. The SGCU is energized from the aircraft electrical APU Starter Generator Description network when the SG is not in operation or from the PMG of the SG when the SG is in operation. The APU FIRE P/BSW de-energizes and electrically disconnects the SG in the Generate mode. the ACLC closes. When the SG is in the Generate APU SG Protection Functions mode. the SG (as the VFGs) includes three generators on the same shaft in the same housing similar to any other generator. The related data is shown on the ELEC AC and APU current to the Auxiliary Generator Line Contactor (AGLC) contactor coil. The SG has a start Electrical connection/disconnection to/from the aircraft main electrical function and an electrical power-generation function. Feeder differential current Open cable APU Starter Generator Management APU SG Interface The Starter Generator Control Unit (SGCU) manages the regulation and protection for the Generate mode of the APU SG. pages of the ECAM SD. the SGCU sends the Power CRDCs to send the status and parameters of the SG in the Generate Ready signal to the ENMU. three phase 230VAC at a Overcurrent constant 400Hz frequency. 17 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . APU GENERATION A350-900 ATA 24 TRAINING MANUAL PAGE . VFG with the VFG installed while the engine is stopped. If the VFG has thermally disconnected. If you operate the 1A (1B. speeds can vary between 9. The cockpit crew must lift the safety guard and The VFG is the normal AC power source used in flight and on ground push the DRIVE P/BSW to energize the VFG-disconnect internal solenoid. This reduces friction induced heat that leads to oil leaks. The V-band clamp assembly is attached to the VFG mounting integral flange. The VFG rotor is directly driven from the engine accessory gear box (AGB) producing a fixed ratio of speed to frequency. Its output is connected to the EPDC through feeders operates when overheating occurs. the engine is off and the steering towing key is not installed. The control and monitoring of these VFG thermal disconnection. The higher the input speed Reengagement of a disconnected unit is a ground operation conducted from the engine. the higher the frequency the VFG will produce. related reset handle. Installation to the AGB is via a dynamic seal that has a stationary carbon seal mating surface with a dynamic input shaft seal that produces pressure to lift the carbon seal off the shaft. A VFG converts mechanical rotating power coming from shaft onto The VFG also has an automatic thermal-disconnection mechanism that electrical power. 2A or 2B) GEN pushbutton switch when Each VFG is installed on the engine gearbox with a V-band clamp fitting. necessary to remove the defective VFG and send it to the applicable workshop. VFG The V-band clamp assembly includes the following: oil-level monitoring-faults can occur. V-band clamp CAUTION. THE ONLY OPTION IS VFG Mounting bolts REPLACEMENT. The defective VFG rotor is then mechanically disconnected from the Each of the generator channels is rated for a continuous capacity of 100 engine accessory gearbox. It is not possible to do a reset after a running via segregated routes. If the troubleshooting is satisfactory.900 (330Hz) rpm up to 26.18 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY VARIABLE FREQUENCY GENERATOR General Description VFG Disconnection/Reconnection The generator is an oil-cooled machine that is driven by the engine The DRIVE P/BSW controls the mechanical disconnection of the VFG. mechanically defective. . FAULT legend of the DRIVE P/BSW comes on when the VFG is The generator is cooled with oil via the integral oil management system. 230 volts over the maintenance personnel can re-connect the VFG to the gearbox with the frequency range of 370 to 800Hz. it is are performing by four GCUs (Generator Control Unit). kVA at the point of regulation (POR). V-band flange NO REENGAGEMENT IS POSSIBLE AFTER A DYNAMIC Tension bolt DISCONNECT.A350-900 ATA 24 TRAINING MANUAL PAGE .00 rpm (867Hz) NOTE: The VFG oil-level measurement-function does not operate if the VFG Installation steering towing key is installed in the Nose Landing Gear (NLG). The gearbox and it is attached to the gearbox-mounting pad utilizing a V-band. three-phases. when the engines are running. 19 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . VARIABLE FREQUENCY GENERATOR A350-900 ATA 24 TRAINING MANUAL PAGE . The Power limit function voltage regulation is done by adjustment of the current supplied to the exciter generator. Each GCU has an ARINC 429 interface with the ELMF hosted in two CPIOMs. When the VFG operates. will disconnect the defective switch status. Over/undervoltage displacing "corkscrew" axis). to/from the aircraft main electrical network and for the reset of GCU protection function The DRIVE pushbutton commands the mechanical disconnection of the The ENG 1 (2) FIRE P/BSWs to de-energize and to electrically VFG. The ENMUs have a CAN interface with their related EDMUs The GEN P/BSW for the electrical connection/disconnection of the VFG that gives the AFDX network interface with aircraft systems. The VFG contains a The GCU has the protection functions that follow: metal alloy substance that when temperature is more than 199+/. the GCU gives order to the the generator field. VFG (mechanically). The crew must then open the safety guard and push the DRIVE pushbutton. Each GCU has an ARINC 429 interface with the AFDX following Pushbutton switches: network through CRDCs to send the status and parameters of the related VFG to the CDS. then the disconnect relay. Over/underfrequency Overcurrent Feeder differential protection .The thermal disconnect is not resettable without VFG disassembly. The GCU (through the OPU) has the full authority on the GLC. overvoltage protection redundancy by opening the related GLC and de- energizes the applicable VFG through removal of the excitation voltage to When the electrical parameters are correct. The related data is shown on the ELEC AC page of the The DRIVE P/BSW for the mechanical disconnection of the VFG ECAM SD. OPU to close the Generator Line Contactor (GLC).20 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY VFG MANAGEMENT General Description Open cable Oil temperature detection Each Generator Control Unit (GCU) and Overvoltage Protection Unit Low oil pressure (OPU) manage the regulation and the protection of their related VFG. after receiving an input Engine Master Switch Status provides a GND/Open input providing master 28VDC discrete signal managed throw EPDC. The FAULT legend of the DRIVE pushbutton comes on to show that disconnect the related VFG the VFG is defective. The VFG is also equipped with a thermal disconnect mechanism which is Protection Functions activated for temperature above 199+/.10º F). GCU. The GCU sends a Power Ready signal to the ENMF (hosted in the ENMU) which gives the Interface Ground/Open signal to the GLC. the OPU supplies the CTs and the PORs.A350-900 ATA 24 TRAINING MANUAL PAGE . The ELMF gives overload protection by automatic commercial- The manual control of the VFG is done through the GCU through the load shedding. the PMG supplies the prevent the disconnect solenoid overtemperature.5º C (390+/.5º C melt. according to the current and voltage values sensed by When the GCU over frequency protection function fails. causing the mechanical disconnect (the role would make the trip coil. The GCU is electrically supplied from the aircraft electrical network when The “Disc request” signal is inhibited by the inhibition relay when needed to the VFG does not operate. 21 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . VFG MANAGEMENT A350-900 ATA 24 TRAINING MANUAL PAGE . VFG-2B and VFG-2A. The GCU2B and the ENMFs (side 2) control and monitor the GLC2B Maintenance Data In order to provide Status/Maintenance Data. the CPIOM and RDC (warning and display use) are transmitted via data GCU sends a power ready signal to the ENMF. Once GLC-XX is closed.A350-900 ATA 24 TRAINING MANUAL PAGE . The corresponding GCU provides the 28VDC to supply the GLCXX coil and ENMF provides a “ground/open” signal. displays and data to ELMF by the interface with the remote data concentrator (RDC) and the electrical load management system (ELMS). The GCU2A and the ENMFs (side 2) control and monitor the GLC2A GLC2B for the AC2B main busbar (200XNB). . VFG-1B. ENM or ELM are transmitted by either discrete signals or data bus (ARINC 429). busbar is supplied. ENMF command is inoperative. two data bus channels (Arinc A429) are used by the GCU for transmission of warnings. EPDC. GLC2B and GLC2A allow the power supply of the 230V The information from GCU to: AC Normal busbars from the VFG-1A. Then the associated AC bus (ARINC 429). the GCU have full authority. The GCU1B and the ENMFs (side 1) control and monitor the GLC1B GLC2A for the AC2A main busbar (200XNA). ICP are transmitted by a discrete signals If one GCU agrees with the connection/disconnection of the GLCXX. The power ready signal is sent when: No protection function operates AND The engine speed is sufficiently high for the VFG AND The voltage level is reached AND The GEN pushbutton is pushed. The GCU1A and the ENMFs (side 1) control and monitor the GLC1A GLC1B for the AC1B main busbar (100XNB). the ENMF cannot open the GLC. The GLCs connect the VFGs to the related network: GLC1A for the AC1A main busbar (100XNA).22 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY VFG MANAGEMENT (CONT) GLC1A. To open the line contactor. GLC1B. 23 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . VFG MANAGEMENT (CONT) A350-900 ATA 24 TRAINING MANUAL PAGE . The oil is collected in the generator sump/reservoir and is drawn away by a pump mounted in a module assembly. When the oil is cold (cold day operation before engine start) this valve is open. In such conditions. and aiming to prevent oil drain back into the VFG at engine shut down. Then. The surface cooler system comprises the following parts: Surface Air Cooled Oil Cooler (SACOC): The cooling matrix which is attached to the bypass side of the rear fan case Oil Pressure Relief Bypass valve (PRV): A valve integrated to SACOC body. . spray cools the diodes and stator overhangs and provides lubrication to both of the bearings. Thermal Bypass A thermal bypass valve is related to each SAOHE. the oil flows from the VFG oil pump through the valve and goes back to the VFG through a VFG Pressure Regulating Valve (PRV). The oil in the centre of the rotor shaft flood cools the rotor windings. before it is returned to the rotor shaft for redistribution within the generator. aiming to control TBV operation Drain back Valve: located upstream VFG oil-in line. the thermal bypass valve goes back to the closed position.24 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY VFG OIL LUBRICATION AND COOLING General Description The generator is cooled with oil supplied via the integral oil management system.A350-900 ATA 24 TRAINING MANUAL PAGE . The pump delivers the oil through a 20-micron filter. the oil flow bypasses the heat exchanger and the oil temperature becomes correct for quicker lubrication. aims to allow the cooler to de-congeal during cold start Thermal Bypass Valve (TBV): this valve aims to ensure full compliance to VFG oil-in temp spec requirements. in particular for cold day operation VFG oil temperature sensor. a surface air cooled oil cooler (SACOC) and another internally housed filter. 25 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . VFG OIL LUBRICATION AND COOLING A350-900 ATA 24 TRAINING MANUAL PAGE . A350-900 ATA 24 TRAINING MANUAL PAGE - 26 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY VFG OIL SYSTEM MONITORING VFG Oil-Filter Monitoring A delta pressure switch monitors the oil filter. It measures the oil pressure at the inlet and outlet of the filter and senses a possible filter clogging condition. The VFG sensors send the low oil level and filter clogging signals to the related Generator Control Unit (GCU). Then, the GCU sends this data to the FWS for low oil level, and CMS for filter clogging. NOTE: The VFG oil-level measurement-function does not operate if the steering towing key is installed in the Nose Landing Gear (NLG). If you operate the 1A (1B, 2A or 2B) GEN pushbutton switch when the engine is off and the steering towing key is not installed, VFG oil-level monitoring-faults can occur. Oil Temperature and Pressure Monitoring Oil temperature sensors monitor generator bearing and outlet oil temperature for over detection. Oil pressure sensors monitor the oil pressure. In the event of the oil overheat or oil low pressure, a signal is sent to the GCU and issue a warning to the flight crew to request a manual disconnect of the VFG. In the event of of low pressure monitoring failure, a dispatch message is sent to inform flight crew. Oil Level Monitoring The low oil level monitoring function determines a low oil level condition by a remote oil level sensor (ROLS). The sensing process is initiated on ground, 6 minutes after engine shutdown or a cold start and in the event of low oil level, a signal is sent to the flight crew but do not cause a protective trip. VFG OIL SYSTEM MONITORING A350-900 ATA 24 TRAINING MANUAL PAGE - 27 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY A350-900 ATA 24 TRAINING MANUAL PAGE - 28 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY VFG OIL SERVICING General Description Sight Glass The servicing of the VFG oil system can be scheduled or unscheduled. The green area shows that the VFG oil level is correct. Scheduled Servicing At the end of the servicing procedure, the oil level must be near the top of this green area. At the specified maintenance schedule interval you may be required to: The yellow area shows that the VFG oil level is above the normal level but Drain and fill the VFG oil system not too high. This often occurs immediately after the engine shutdown Replace the oil filter when the engine oil is hot. Unscheduled Servicing The upper red area shows that there is too much oil. You must drain oil to get the correct oil level. Unscheduled servicing may be required to: The lower red area shows that the oil level is not sufficient. You must do the servicing and add oil until the oil level is at the top of the green area. Add oil if the level is low, or if you replaced a system component Drain the system before you replace the VFG Magnetic Drain Plug Fill the system if you drained a VFG, or after oil contamination The magnetic drain plug has a magnet that collects metal particles that can Overfill Connection be checked in order to monitor the VFG status. The connection of an overfill drain hose to the overfill drain port The magnetic drain plug can be loosened: to decrease the oil level, if it is depressurizes the VFG case. above the correct level after filling. It can also be removed: to drain oil from the VFG or the system. When the oil flows from the overfill drain hose, you must continue to fill slowly until approximately one quart of oil drains into the oil container. Replace the related O-ring at the removal/installation. NOTE: Do not forget to connect the overfill drain hose before you fill the oil. Filter Cartridge If not, an overpressure of the VFG case will occur and cause a fault status of the VFG. The filter cartridge can be removed for scheduled replacement or an inspection if there is oil contamination. Pressure Fill Connection Replace the related O-ring at each removal/installation. An oil servicing pump is used to add oil or to fill the system. It is connected to the pressure fill port through a pressure fill hose. 29 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . VFG OIL SERVICING A350-900 ATA 24 TRAINING MANUAL PAGE . The essential purpose of the normal batteries is to ensure the NBPT function (No Break Power Transfer). The normal DC network is a network without power supply interruption as soon as the batteries P/B are selected ON and no batteries fault. It is able to deliver 300A. current and voltage sensors) (BAT-1 and BAT-2) The TRU is an AC/DC converter. . The main DC bus bars can be connected through the contactor BTDC to allow DC reconfiguration in case of TR failure and to ensure the entire availability of the normal DC network with only 1 VFG remaining. to start the APU when no AC power is available and energize the DC network for the specific modes on batteries (Towing and Refuel).A350-900 ATA 24 TRAINING MANUAL PAGE . The normal batteries are not considered as power source for DC network. protection with temperature. The DC1-100PN and DC2-200PN are the main Normal DC bus bars. It provides an unregulated voltage to the DC network. load control. They are supplied through TR-1 and TR-2. and secondary power distribution boxes SPDB. continuously with a voltage of 28VDC when extracted. The normal batteries are also connected on these bus bars to ensure the NBPT (No Break Power Transfer) function.30 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY DC NORMAL GENERATION General Description The 28 V DC normal network (No Break Power Transfer) is supplied by: 2 Transformer Rectifier Units (TR-1 and TR-2) (230VAC / 28VDC converter) 2 batteries (Ni-Cd technology. The normal DC electrical power is distributed by the main power center EPDC (side 1 and 2). supplied by the A/C 230V network and are identical and interchangeable. DC NORMAL GENERATION A350-900 ATA 24 TRAINING MANUAL PAGE .31 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . The TRU cooling is ensured by aircraft cooling and can work in two modes. or the recovery after an AC The second. the Point Of and to the communication Measurement (POM) value and two signals that give the status of the TLC −An AC/DC converter module (TLC status and inverse TLC status). this module is dedicated to the contactor control logic The TRs receive from the EPDCs the emergency condition. which is supplied from the normal AC network. messages to the flight crew The RESET ICPs to transmit the reset signal to the TRs The control board of TRU is supplied from three independent power The Central Maintenance System (CMS) A through the Secure sources: Communication Interface (SCI) to collect maintenance data The Data Loading and Configuration System (DLCS)A through the SCI The first is provided by an AC/DC converter module. Back-up TLCs contactor is driven exclusively by their respective TR. the TRU is able to through the CRDC for the ground/flight signal provide 175 A in flight and 55 °C maximum temperature or 155 A The Flight Warning System (FWS) through the CRDC to show warning on ground and 70 °C maximum temperature. one at the time. The Landing Gear Extension and Retraction System (LGERS) A Without A/C cooling or in loss of cooling mode (= 0g/s).A350-900 ATA 24 TRAINING MANUAL PAGE . It provides an unregulated voltage to the DC network. The Control and Display System (CDS) through the Common Remote Data Concentrator (CRDC) With A/C cooling normal. Each TR is supplied by its related TR2 supplies 28VDC busbar DC2 through TLC2 230VAC main busbar: Each TR controls the connection/disconnection of its related TLC. to supply the components of TRU-PCB. The TRs also interface with the following aircraft systems: with A/C cooling if in main position or without A/C cooling if in emergency position or in main position and loss of cooling. −A control board. availability does not depend on AC availability The third is provided by the 28VDC at the TRU output One of three available 28VDC Power Supply is used.32 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY TRANSFORMER RECTIFIER (TR) Overview Each TR supplies its related 28VDC main busbar: The DC main generation system has two Transformer Rectifiers (TRs) that TR1 supplies 28VDC busbar DC1 through TR Line Contactor 1 (TLC1) are the same and interchangeable. The TRs have an interface with the Electrical Power Distribution Center The TRU is composed of: (EPDC). supplied by the A/C network. The TRU is an AC/DC converter. . called back-up. TRU can provide 300 A to the DC network. To speed up the DC network power up phase. is supplied by the hot bus (directly power interruption and avoid the double command from the EPDCs. It is able to deliver 300A Interfaces continuously with a voltage of 28VDC. the connected to the battery busbar via a relay and a breaker). 33 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . TRANSFORMER RECTIFIERS A350-900 ATA 24 TRAINING MANUAL PAGE . Battery monitoring is perfomed by the Battery Management Unit (BMU-1 and BMU-2) installed separately from the battery. . The TOWING ON BAT section of the maintenance panels can give the charge level of the battery 1.A350-900 ATA 24 TRAINING MANUAL PAGE . The battery uses nickel-cadmium (Ni-Cd) technology. with a full- charge capacity of 50 Ah for a voltage of 24 V. The battery functions as follows: NBPT to keep the 28VDC available at the related 28VDC busbars during electrical power transfers and/or electrical network reconfigurations Start of the APU when no AC main power source (external power or Variable Frequency Generator (VFG)) is available Supply of part of the DC network for refuel on BAT and towing on BAT procedures Management of their charge status and related charge cycles Internal overcurrent and overdischarge protection On the overhead panel the BAT section of the maintenance panels gives the voltage of all the batteries in all configurations.34 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY MAIN BATTERIES (NI-CD) General Description Two main batteries (BAT1 and BAT 2) are connected to main DC busbars: BAT1 on 100PN and BAT2 on 200PN. The battery uses Ni-Cd technology and consists mainly of 20 Nickel Cadmium cells housed in a stainless steel box with 2 vents and two handles. All monitoring and interface with the aircraft are performed by the BMU outside the battery. 35 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . MAIN BATTERIES (NI-CD) A350-900 ATA 24 TRAINING MANUAL PAGE . The sum of current values shall never exceed a specified limit. activation or by thermistor (temperature above 73ºC). An external current sensor (shunt) provides battery output current. If the sum of the battery and TRU currents is higher than the specified limited. The overtemperature protection is generated through two Main battery 1 and emergency battery 1 are located on the left side of the different signals from battery. Only the When BMU detects an overtemperature or internal short-circuit condition. it Normal Mode BITE is available to produce maintenance diagnosis. the BMU sends a OVERDISCHARGE discrete signal to the EPDC that opens the BATLC battery contactor. . measured through the related shunt and sent to the related BMU. MONITORING & PROTECTION General Description Each BMU manages its related battery: BMU monitors battery parameters and provides to the EPDC information BMU1 for Battery 1 about overdischarge and failure signals. As for Li-ion batteries. Outside of each battery there is a fuse that ensures wiring protection between the battery and current sensor. an ARINC signal is sent to the FWS trough the CRDC. a discrete signal is sent to EPDC in order to measurement) and sent to the related BMU. Location BMU provides batteries protection in case of overtemperature and internal short-circuit. Battery provides temperature BMU2 for Battery 2 (through a thermistor) and voltage information to the BMU. There is no BITE interactive mode for Ni-Cd configuration. the DC protection implemented in the ENMF (located on EPDC) measures currents of the Battery and TRU. Additionally. the ENMF force to open the BATLC and then the TRU clarify the short circuit by opening the TLC contactor. Main battery 2 and emergency battery 2 are located on the right side of the The overtemperature protection is driven either by thermal switch avionics compartment. a thermistor that provides BMU with battery avionics compartment.36 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY BATTERY CONTROL.A350-900 ATA 24 TRAINING MANUAL PAGE . temperature and a thermal switch that activates when temperature is above 71ºC. Interface with CMS and CRDC The current measurement is used to monitor the battery output current and provide BMU with the current for the battery internal short circuit detection. In case of battery undervoltage condition. sends a FAULT discrete signal to the EPDC that opens BATLC battery contactor. The current measurement is disconnect the battery from the network and to ICP battery P/B switch. The battery parameters (temperature. voltage and current) are measured through sensors integrated in the battery (except the shunt for the current In case of battery failure. 37 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . MONITORING & PROTECTION A350-900 ATA 24 TRAINING MANUAL PAGE . BATTERY CONTROL. 38 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY BATTERY SHUNT Student Notes: .A350-900 ATA 24 TRAINING MANUAL PAGE . BATTERY SHUNT A350-900 ATA 24 TRAINING MANUAL PAGE .39 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . A350-900 ATA 24 TRAINING MANUAL PAGE .40 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY NI-CD BATTERY COMPONENT LOCATION Student Notes: . 41 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . NI-CD BATTERY COMPONENT LOCATION A350-900 ATA 24 TRAINING MANUAL PAGE . The shaft driven generator assembly provides three-phase. The generator Strut leg assembly is rated to provide 40 KVA continuous output at POR. Generator 28 VDC essential network through TR-EMER.780 RPM. the emergency Transformer Rectifiers (TRs) supply the DC emergency network. related emergency network is installed in the Electrical Power Distribution System (EPDS). the following consumers: deployed. The RAT Stow Panel is located in the Green Ground Service Panel (GGSP) within the left hand belly fairing thereby allowing for RAT stow only For the 230VAC power. Total Engine Flame Out (TEFO) or Loss of The Line CTA (Current Transformer Assembly) is located inside EPDC-2 in Main Electrical Supply (LMES). monitoring of the RAT is via EPDC-2. In the emergency configuration. with the Ram Air Turbine (RAT) deployed. ground in battery only configuration. Fuel electric pumps. A Permanent Magnetic Generator (PMG). the RAT will provide For the 28VDC power. on the ground. nominal output to emergency equipment in the event that is located on the right hand side AFT belly fairing. retraction operation.42 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY AC AND DC EMERGENCY GENERATION General Description aircraft emergency equipment bay inside the pressurized vessel. Miscellaneous loads. the static inverter supplies 115VAC to 115VAC busbar AC EMER. integral to the generator assembly. . at aircraft speeds Gearbox above 140 KEAS. 235 / 407 V The AC emergency generation system is composed of the RAT module. in normal configuration. In emergency configuration. or on the deployed. regulates. each emergency Auto Transformer Unit (ATU) supplies its ground in battery only configuration. Primary Flight Control Electro-hydraulic Actuators (EHA & EBHAs) on the three A/C control axis. is comprised of: of total loss of the normal AC electrical power generation system. each emergency battery supplies its related DC emergency network. For the 115VAC power. When one of the above-mentioned events is declared. at aircraft 2-bladed Turbine speeds above 175 KEAS.A350-900 ATA 24 TRAINING MANUAL PAGE .800 to 10. in normal or emergency configuration with the RAT In emergency configuration during RAT deployment in flight. It provides control and monitoring functions for the RAT’s 2B supply the emergency network. the contactor cabinet on the upstream side of the EGLC. during RAT deployment in flight or on the Slat electric motor. All control and the RAT generator supplies all of the AC and DC emergency network. and 50 KVA continuous output at POR. 389 to 539 Hz. 230VAC busbar AC 1B. RMS. at least. The Generator Control Unit (RAT GCU). controls and protects the output voltage of the RAT System automatically There is an AC and DC emergency electrical generation system. a part of the AC emergency network on 115VAC busbar INV AC1. Frame assembly provides the necessary power to operate the GCU. in normal or emergency configuration with the RAT 230 VAC power. which is located remotely in the The generator is air cooled through an intake on the strut leg. The when the RAT is deployed. Deployment Actuator with integral uplock and integral downlock Electrical Generator Nominal generator operating speed is 7. 43 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . AC AND DC EMERGENCY GENERATION A350-900 ATA 24 TRAINING MANUAL PAGE . a discrete signal is sent to the EPDC. element is sequentially powered depending on the flight phases when the aircraft is in the air. Heaters are supplied by means of two SSPCs 115VAC (one SSPC per heater). WARNING: IT IS POSSIBLE TO DEPLOY THE RAT ON THE GROUND. The RAT must be deployed manually when the automatic deployment does not operate during emergency conditions (TEFO or LMES) or during the manual test procedure. EMER HOT BUS 2 energizes the auto/manual deploy solenoid.44 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY RAT DEPLOYMENT AND GENERATOR HEATING General Description Generator Heaters The deployment of the RAT can be automatic or manual. which supplies 28VDC to the auto/manual solenoid. and it is not controlled or monitored by the RAT system. with the RAT stowed. BEFORE YOU DO A MAINTENANCE OPERATION IN THE RAT AREA. related to a loss of the four main AC busbars TEFO. as determined from the aircraft on-ground / in-flight Automatic Deployment status logic. related to a loss of the two engines The Electrical Power Distribution Center (EPDC) receives emergency condition data and sends an output signal to control the automatic deploy solenoid and the auto/manual deploy solenoid. When the RAT MAN ON pushbutton switch is pushed. EVEN ON A DE-ENERGIZED AIRCRAFT BECAUSE THE AUTO/MANUAL SOLENOID IS SUPPLIED FROM EMER HOT BUS 2.A350-900 ATA 24 TRAINING MANUAL PAGE . one solenoid for the automatic machined into the outside surface of the main stator. EMER HOT BUS 1 energizes the automatic deploy solenoid. the flight crew can push the guarded RAT MAN ON pushbutton switch. YOU MUST PUT THE RAT SAFETY PIN IN POSITION. LMES. if there is one of the emergency busbar to the heater 1 and from CBP-2 via 200XPB Normal busbar to the conditions that follow in flight: heater 2. . The heaters are responsible for the avoidance of icing in the generator. Manual Deployment To deploy the RAT manually. The two redundant generator heating elements are bonded into grooves Two solenoids control the deployment. from EPDC-2 via 200XPA Normal The RAT is deployed automatically. Each heater control and one solenoid for the auto/manual control. . RAT DEPLOYMENT AND GENERATOR HEATING A350-900 ATA 24 TRAINING MANUAL PAGE - 45 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY A350-900 ATA 24 TRAINING MANUAL PAGE - 46 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY RAM AIR TURBINE - DEPLOY Deployment In the unlikely event that a stow command is given and the downlock mechanism fails to disengage, the resultant force from hydraulic When commanded automatically by the aircraft system or manually by the pressure acting on the locked piston actuator will not damage any parts of pilot, one of the actuator deploy solenoids is activated and the actuator - the actuator. extending under the action of a spring forces- releases the strut leg and turbine into the airstream. Once deployed, an integral downlock device maintains the actuator in the extended position under any flight load. During RAT deployment, the actuator acts as a structural member (primarily in tension) to resist the effects of aircraft acceleration loads, aircraft door aerodynamic loads, turbine drag loads and RAT vibration loads. The RAT may also be deployed when the aircraft is on the ground for purposes of maintenance and ground checkouts. Stow / Retraction Hydraulic pressure causes the downlock mechanism to release and the actuator to retract. The actuator is controlled by a solenoid integral to the stow control valve module. Electrical power to the solenoid is from the RAT stow panel. The stow control valve module controls fluid flow during actuator retraction. An integral pressure switch provides indication of actuator pressure above a threshold value. The stow control valve module is located in the actuator cylinder head, and consists of the following: High pressure hydraulic port is connected to the aircraft high pressure system Low pressure hydraulic port is connected to the aircraft hydraulic suction line Stow solenoid Restow Orifice Control valve Actuator pressure switch Stowed position switch RAM AIR TURBINE - DEPLOY A350-900 ATA 24 TRAINING MANUAL PAGE - 47 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY return to its deployed position. the RAT STOWED and ACTUATOR position. The RAT stow panel is located in the Green Ground Service Panel within the left hand belly fairing. the switch energizes a green hydraulic solenoid mechanically stopped and the switch has to be released for the RAT to valve that allows to retract the RAT module. When the switch is held in the stow position. Actuator Pressure LED illuminated. The red ACTUATOR PRESSURE indicator light comes on when the actuator is pressurized. then the stow is In the STOW position. guard-protected. This switch controls power supply to the stow panel. Retraction Sequence Description Logic/Stow Panel Indication The RAT can retract in the conditions that follow: Open – On increasing pressure at 50 bars relative.off toggle are used to control and monitor the RAT retraction sequence. It has two switches and two indicator lights that The stow/lamp test switch is a 3-position. As it is a three-position switch. If the switch is inadvertently completed. Actuator Pressure 28VDC is available LED not illuminated. RAT Stowed Indication The on / off switch is a 2-position. therefore if the switch guard is in the up position the panel door cannot be closed. center. A350-900 ATA 24 TRAINING MANUAL PAGE . left in the ON position. The combined STOW/LAMP TEST switch is a three-position switch. Green hydraulic system is pressurized STOW/LAMP TEST switch is in the STOW position The stow panel on / off switch does not need to be in the on position for the LED to be illuminated. spring If the switch is released prior to the RAT completing the stow operation.STOW Stow Panel Description guard as the door is closed. the loaded to the neutral center position: stow solenoid will be de-energized and the actuator will re-deploy to its extended position. RAT turbine blades are correctly aligned Closed – On decreasing pressure at 20 bars relative. If the turbine is not aligned. The switch must be held in the STOW position until the RAT is 28VDC. and actuator pressure is above the following threshold values. the stow panel door will contact with the switch . 28 VDC is sent to the actuator stow solenoid causing hydraulic pressure to retract the RAT The guarded ON/OFF switch is used to supply the RAT stow system with actuator. providing a lamp check function. Led Indica ons The green RAT STOWED indicator light comes on when the RAT is fully The Actuator Pressure LED is illuminated whenever the aircraft is powered stowed and locked. The on / off switch must be The RAT stowed indication is illuminated when the stow process has been in the ON position to perform stow operations. fully stowed and locked. moving it to the OFFposition.48 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY RAM AIR TURBINE . the alternate In the LAMP TEST position. spring-centered. switch. toggle switch. Moving this switch to the lamp PRESSURE indicator lights are on. A viewing window on the stow panel door permits observation by ground personnel when the overlying aircraft access door is Control of the stow panel is accomplished with two switches mounted on the removed face of the panel under the panel door. test position illuminates the indicator LEDs providing verification to the user that the indicators are functional. RAM AIR TURBINE .49 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY .STOW A350-900 ATA 24 TRAINING MANUAL PAGE . In this configuration. the EGLC opens and the RAT generator is de-excited. The RAT Generator supplies AC emergency busbars until the end of the When the electrical parameters are correct. the Protection Functions FAULT light goes off. Emergency Generator Line Contactor (EGLC) to close. This condition occurs during the RAT deployment. The RAT GCU is energized from the aircraft electrical network (28VDC) for Interface BITE when the RAT does not operate or by the PMG when the RAT operates.A350-900 ATA 24 TRAINING MANUAL PAGE . In generator. a A Permanent Magnet Generator (PMG) protective inhibit signal is sent from EPDC2 to the RAT GCU to cancel all An exciter generator the RAT GCU protection functions. the RAT generator continues to supply electrical power even in degraded mode. These protection functions are for the RAT The RAT generator includes three generators on the same shaft in the generator ground tests only. The RAT GCU has an AFDX network interface with the CDS through the CRDC to send and show the RAT generator status and parameters on the The RAT generator properties are related to the aircraft speed: ELEC AC page. the RAT generator has the priority The RAT GCU manages the regulation and protection for the RAT on its emergency channel even if there is another main power source. Output voltage three-phases 230VAC The RAT GCU has an interface with the cockpit EMER ELEC PWR panel Frequency: from 360Hz to 800Hz to cause the FAULT light to come on when there is an electrical Power rating: 50 kVA when the aircraft speed is more than 175 Kts. the RAT GCU causes the flight and the emergency network is fully isolated regarding the normal one. if APU and/or VFG(s) are recovered after RAT deployment.GENERATOR MANAGEMENT General Description When the RAT GCU triggers protection function. emergency condition and the EGLC contactor stays open. The RAT GCU has these protection functions: Overvoltage Undervoltage Differential current Overcurrent . same housing: In flight and in emergency condition (information given by A/C systems). The Emergency network never supplies the normal network. A main generator In order to avoid two parallel supplies. Regulation (POR). The voltage regulation is operated through the adjustment of the flight. the same current supplied to the exciter generator in relation to current and voltage logic rules as in normal flight will be followed for main normal busbars values sensed by the Current Transformers (CTs) and the Point Of supply.50 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY RAM AIR TURBINE . but when the EGLC is closed. GENERATOR MANAGEMENT A350-900 ATA 24 TRAINING MANUAL PAGE .51 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . RAM AIR TURBINE . 52 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY STATIC INVERTER AND EMERGENCY ATU Static Inverter The static inverter has monitoring for: The static inverter. the output frequency stays the In flight. the primary function of the static inverter is to manage the time same as the input frequency. Some equipment powered from the Static Inverter (391XC/INV AC1) They have a different power rating. The RAT generator is not available for some seconds before the RAT is fully deployed and turns in the air stream. Underfrequency when RAT is not available. . and when emergency The two emergency ATUs are the same and interchangeable. During this short period of time. The dimensions of the emergency ATUs are different. In “PDMI on batteries configuration” on ground when no main electrical Their operation is the same as that of the main ATUs with the following power source is available. The static inverter also supplies electrical power to some loads on the ground when the BAT EMER 1 pushbutton switch is pushed and no AC power is available. and when PDMI on battery mode is exceptions: requested (maintenance only function). located in the avionics bay. necessary between a major failure of the normal AC supply (LMES/TEFO condition) and the connection of the RAT generator to the emergency network. the static inverter keeps the AC electrical power available for some loads connected to the 115VAC busbar INV AC1. include one SCI.A350-900 ATA 24 TRAINING MANUAL PAGE . and RAT not available. Power of 4 kVA Frequency range from 360Hz to 800Hz. one EEC channel and one engine The emergency ATUs are used only for the transformation of the ignition channel for engine relight in case of electrical emergency 230VAC into 115VAC. typically during RAT deployment (around 5sec) Emergency ATU In “normal configuration” on ground during aircraft power on when no main electrical power source is available. the ASFC and OSFC. Emergency ATUs' properties are: It changes the 28VDC from emergency battery 1 into single phase 115VAC fixed 400Hz. rated to 500 VA. configuration/ TEFO. is used to supply part of the Overheating 115VAC emergency network (391XC/INV1) AC1 from emergency battery 1 Overvoltage in several specific cases: Undervoltage Overfrequency In electrical emergency configuration (normal electrical sources loss). batteries pushbutton are selected ON. 53 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . STATIC INVERTER AND EMERGENCY ATU A350-900 ATA 24 TRAINING MANUAL PAGE . Location of the EMER TR1 and EMER TR2 Pushbuttons Each emergency TR is supplied by its related 230VAC busbar: The EMER TR1 pushbutton is on the overhead panel. they are not cooled from the avionics ventilation system. supply. the emergency TR1. their primary functions are: Flight Warning System (FWS) through the CRDC to show warning messages to the flight crew Change the 230VAC into 28VDC RESET ICPs to transmit the reset signal to the emergency TRs Control the related Emergency TR Line Contactor (ETLC) Central Maintenance System (CMS) through the Secure Provide protection against overcurrent Communication Interface (SCI) to collect maintenance data Fault detection Data Loading and Configuration System (DLCS) through the SCI Interface with the CDS ELEC DC page through the CRDCs Electrical Power Distribution Center (EPDC) The emergency TRs are the same as the main TRs but when installed as The emergency TRs send to the EPDCs the ETLCs commands and emergency TRs. Rectifiers (TRs) that are the same and interchangeable. Each emergency TR supplies its related 28VDC emergency busbar: Interfaces Emergency TR1 supplies 28VDC busbar DC EMER 1 through The DC emergency generation system has an interface with: Emergency TR Line Contactor 1 (ETLC1) Emergency TR2 supplies 28VDC busbar DC EMER 2 through ETLC2 Control and Display System (CDS) through the Common Remote Data Concentrator (CRDC) Each emergency TR controls the connection/disconnection of its related ETLC.54 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY DC EMERGENCY GENERATION General Description On the RESET sections of the overhead panel. variable or fixed frequency TLC (TLC status and inverse TLC status).A350-900 ATA 24 TRAINING MANUAL PAGE . the TRU fault to tell that TRU is disconnected and the overcurrent signal to prevent new configurations. Output voltage of 28VDC Maximum continuous power (on the ground) of 155 A . 230VAC busbar AC EMER 2 supplies emergency TR2 The EMER TR2 pushbutton is on the overhead panel. The properties of the emergency TRs are as follows: The emergency TRs receive from the EPDCs the emergency condition and the Point Of Measurement (POM) value and two signals for the status of Input voltage of 230VAC. 2 switches are used to do the reset of the protection functions of the The DC emergency generation system has two emergency Transformer emergency TRs. on the ICP 232VM. Landing Gear Extension and Retraction System (LGERS) through the CRDC for the ground/flight signal The two emergency TRs are the same. on the Integrated 230VAC busbar AC EMER 1 supplies emergency TR1 Control Panel (ICP) 231VM. DC EMERGENCY GENERATION A350-900 ATA 24 TRAINING MANUAL PAGE .55 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . They have the primary functions that follow: No Break Power Transfer (NBPT) (to keep the 28VDC available at the related 28VDC busbars EMER during electrical power transfer and/or electrical network reconfigurations) Energizing of a part of the DC emergency network for specific modes: Power Distribution Maintenance Interface (PDMI) on battery and evacuation Supply of the static inverter when no AC power is available (emergency battery 1 only) Supply of their related 28VDC busbar DC EMER in emergency configuration (normally during RAT extension after LMES) Management of their charge status and related charge cycles Internal overcurrent and overdischarge protection Interface with the cockpit overhead maintenance panel for battery voltage Interface with the CDS ELEC DC page through the CRDCs Interface with the FWS and CMS application for failure detection and fault reporting/analysis The emergency batteries and the main batteries are fully interchangeable.A350-900 ATA 24 TRAINING MANUAL PAGE .56 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY EMERGENCY BATTERIES (NI-CD) General Description The two emergency batteries are the same. The control and operation is similar to the Main Batteries. . EMERGENCY BATTERIES (NI-CD) A350-900 ATA 24 TRAINING MANUAL PAGE .57 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . A350-900 ATA 24 TRAINING MANUAL PAGE . with a full-charge these conditions: capacity of 50 Ah for a voltage of 24 V. The battery emergency-generation system supplies electrical power in The battery uses nickel-cadmium (Ni-Cd) technology. In normal conditions: The battery has these electrical and mechanical components: If the Alternating Current (AC) electrical power stops.58 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY EMERGENCY BATTERY CONTROL & INDICATION The function of the battery emergency-generation system is to supply Each emergency BMU receives from its related emergency battery shunt 28VDC electrical power to the Direct Current (DC) emergency network. the current measurement data. and interchangeable The emergency BMU is an electronic box which manages the emergency When the AC power sources are available. Each emergency BMU manages its related emergency battery: Emergency BMU1 for emergency battery 1 Emergency BMU2 for emergency battery 2 Each emergency BMU receives from its related battery the following data: Temperature measurement Voltage measurement Thermo-switch status . connected to its related 28VDC emergency busbar through the emergency Battery Line Contactors (BATLCs): The function of the emergency BMU is to: Emergency battery 1 is connected to 28VDC busbar DC EMER 1 Ensure protection against battery failures or battery overdischarge through emergency BATLC1 Manage battery parameters received from the related emergency Emergency battery 2 is connected to 28VDC busbar DC EMER 2 battery and emergency shunt through emergency BATLC2. each emergency battery is battery. Handles In emergency conditions: Vents to remove hot air from the emergency batteries During the extension of the Ram Air Turbine (RAT) DC power connector During the extension of the Main Landing Gear (MLG) Signals connector The battery emergency-generation system has these components: The emergency battery parameters (temperature and voltage) are measured through sensors integrated in the emergency battery and sent to the related emergency BMU. The current measurement is measured Two emergency batteries that are the same and interchangeable through the related emergency shunt and sent to the related Two emergency Battery Management Units (BMUs) that are the same emergency BMU. during a power up phase or for maintenance. or On the ground. EMERGENCY BATTERY CONTROL & INDICATION A350-900 ATA 24 TRAINING MANUAL PAGE .59 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . and by the Ram Air Turbine (RAT) generator in case of electrical emergency configuration (i. 12 Secondary Power Distribution Boxes (SPDB) which ensure secondary distribution (low current < 15A) to non-essential loads (AC and DC) 2 Circuit Breaker Panels (CBP) which provide secondary distribution (low current < 15A) for essential loads (AC). It is supplied by normal network in normal configuration. The electrical network is divided into two segregated parts The Normal network. which is divided into emergency side 1 and emergency side 2. is dedicated to emergency loads necessary to complete a flight and make a safe landing. and emergency distribution for emergency loads (DC). Primary distribution (high current > 15A) to essential and non-essential loads (AC and DC) Non-essential load = cargo/cabin loads Secondary distribution (low current < 15A) for essential loads (AC and Emergency load = “minimal loads” needed to ensure safe flight and DC) landing Emergency distribution to emergency loads (AC and DC). . Primary distribution = distribution to high current loads (> 15A) The electrical distribution system is composed of 2 Electrical Power Secondary distribution = distribution to low current loads (< 15A) Distribution Centers (EPDC) which ensure: And also. which is divided into normal side 1 and normal side 2. Auxiliary Power Unit Generator (APU-GEN)) and/or External Power (EP). The Emergency network.60 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY AC AND DC DISTRIBUTION . from onboard sources (Variable Frequency Generator (VFG).COMPONENT LOCATION Electrical Network Architecture Definition The Electrical Power Distribution System (EPDS) supplies electrical power Electrical loads are categorized depending on their rating: to all the users from the Electrical Power Generation System (EPGS).e. supplies all essential (technical) and non-essential (commercial/cargo) loads. Total Engine Flameout or Loss of the Main Electrical System in flight).A350-900 ATA 24 TRAINING MANUAL PAGE . depending on their use Essential load: technical loads. AC AND DC DISTRIBUTION .61 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY .COMPONENT LOCATION A350-900 ATA 24 TRAINING MANUAL PAGE . seats equipment. the emergency distribution parts of the EPDC and CBP supply electrical power to the emergency loads.. Contactors On each side. through the SSPCs. These electrical loads are distributed through the protection and/or switching devices that follow: Solid State Power Controllers (SSPCs) and circuit breakers for the EPDC SSPCs for the CBP NOTE: The technical loads less than or equal to 15 A are non-commercial loads used for the aircraft systems. six SPDBs supply remote electrical power to the cabin and Remote Control Circuit Breakers (RCCBs) cargo loads that have an electrical power consumption of less than or Circuit breakers (C/Bs) equal to 15 A. . the secondary distribution parts of the EPDC and CBP supply electrical power to the technical loads that have an electrical power consumption of less than or equal to 15 A. Each EPDC primary-distribution part also supplies electrical power to: The electrical power supplied by the SPDBs comes from the primary distribution part of each EPDC. The related secondary and emergency distribution parts NOTE: The cabin and cargo loads are commercial loads (for example the The six SPDBs for decentralized distribution In-Flight Entertainment (IFE))..62 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL POWER DISTRIBUTION General Description These electrical loads are distributed through the protection and/or switching devices that follow: For each side of the EPDS.. For each side. cargo loading/unloading. the primary distribution part of the EPDC supplies electrical power to technical loads which have an electrical power RCCBs and contactors for the EPDC consumption of more than 15 A.A350-900 ATA 24 TRAINING MANUAL PAGE . For each side. Circuit breakers for the CBP These electrical loads are distributed through the protection and/or NOTE: The emergency loads must stay energized in the emergency switching devices that follow: electrical configuration. 63 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . ELECTRICAL POWER DISTRIBUTION A350-900 ATA 24 TRAINING MANUAL PAGE . The Electrical Discrete Interface Unit (EDIU) acquire CB statuses. EDMU function performs the following functions: Electrical Network Management Unit (ENMU) Communication Interface management between EPDS and other Two redundant ENMU cards are implemented in each EPDC. CDS. and is composed of two segregated parts: ATU.g. FSA-NG) units are dedicated to the normal electrical network management Control and commutation functions for SSPC/RCCB and perform the following main functions: Monitoring of all Protection/Commutation Devices (P/CD) Load shedding orders management Compute the normal electrical network configuration according to Gather all main EPDC boards monitoring data (e. One EDIU is implemented in each source overload signal). and the other part (EDIU A) dedicated to normal CB status monitoring (discrete signals for SSPC commands and/or utilities function are shared by both part) External Power Control Unit (EPCU) The EPCU manages the External Power (EP) and ensure the electrical network protection depending on electrical characteristics (voltage/frequency/current) of power delivered by the EP. Load shedding (in case of source overload. and manage the two and CBP normal ATU of the related side through two segregated channels.64 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL POWER DISTRIBUTION CENTER COMPONENTS 1 Electrical Distribution Management Unit (EDMU) ATU Protection Unit (ATUPU) Four EDMU cards are implemented in each EPDC. EPCU) sources availability and network parameters. EDIU is divided in two sub parts: one part dedicated to emergency CB status monitoring (EDIU B). ENMU. and other discrete Manage all signals related to normal network (e. Monitor the AC and DC contactor. One EPCU is implemented per EPDC (one EP per side) . ICP commands.A350-900 ATA 24 TRAINING MANUAL PAGE . Two EPDC EDMU which manages the electrical loads within the EPDC One ATUPU is implemented per EPDC. EPDC. and normal network. EDMU cards The ATUPU ensures normal ATU protection depending on electrical manages the electrical loads of the EPDS and interfaces the EPDS characteristics (voltage/frequency/current) of power delivered by the with the aircraft systems.g.g. Two SPDB EDMU which manages the electrical loads within the SPDB Remark: Emergency ATU are managed by EENMU. These aircraft systems (e. and ATU monitoring. or on configuration) discrete commands used for SSPC control. inputs for utilities functions. FWS. Configure the normal network by managing the associated contactors Electrical Discrete Interface Unit (EDIU) (AC and DC). 65 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . ELECTRICAL POWER DISTRIBUTION CENTER COMPONENTS 1 A350-900 ATA 24 TRAINING MANUAL PAGE . A350-900 ATA 24 TRAINING MANUAL PAGE .g.g. Electrical emergency configuration signal.66 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL POWER DISTRIBUTION CENTER COMPONENTS 2 Emergency Electrical Network Management Unit (EENMU) Two redundant EENMU cards are implemented in each EPDC. convert them in order to supply all EPDC hardware boards (e. and emergency network Manage all signals related to emergency network (e. ENMU. contactors statuses) Ensure ATU-EMER protection depending on electrical characteristics (voltage/frequency/current) of power delivered by the ATU-EMER Safe Redundant Power Unit (SRPU) Two SRPU are implemented in each EPDC. RAT available signal. . These units are dedicated to the emergency electrical network management and perform the following main functions: Compute the emergency electrical network configuration according to sources availability and network parameters Configure the emergency network by managing the related contactors (AC and DC) Monitor the AC and DC contactor. EPCU. except EENMU boards which have dedicated power supply directly derivate from sources. These power units gather AC and DC power supply from electrical sources. ATUPU). ELECTRICAL POWER DISTRIBUTION CENTER COMPONENTS 2 A350-900 ATA 24 TRAINING MANUAL PAGE .67 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . the ELMF exchanges data through the AFDX network with: EPDCs and CBPs. The EENMF manages the connection and disconnection of the emergency power sources in relation The EPDCs have the functions that follow to manage their related side: to their availability. the EENMUs and the ESBF AFDX network through the CRDC.A350-900 ATA 24 TRAINING MANUAL PAGE . The ELMF manages the automatic BITE function through the CPIOMs that host the Electrical System BITE shedding of some cabin loads to prevent overload of the EPGS generators Function (ESBF) in relation to their availability to supply the electrical network (for example before a high-consumption user such as an Electrical Motor Pump (EMP) Communication is started to pressurize the hydraulic system). The EPDC and CBP components communicate inside and outside of the To do this. Management of the distribution network Management of the electrical loads to prevent overload conditions Electrical Load Management Function (ELMF) through the Electrical Load Management Function (ELMF) hosted by the CPIOMs The ELMF is hosted in two CPIOMs. ENMF CDS to show shedding data. The EENMF controls the emergency distribution contactors and thus determines the emergency electrical network Protection of the distribution network configuration and manages the reconfigurations as necessary. All the EPDC and CBP components (electronic cards) communicate internally through the EDMUs. ENMF controls the primary distribution contactors and thus determines the ENMF for reconnection data and the ELMF hosted in the same CPIOMs. . as applicable The AFDX network is used for communications with: Electrical System BITE Function (ESBF) The OIS that hosts the Power Distribution Monitoring and Maintenance Function (PDMMF) and the DLCS The ESBF is hosted in two CPIOMs. The external communications EPDCs are between the EDMUs and the AFDX network.68 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL POWER DISTRIBUTION CENTER FUNCTIONS Emergency Electrical Network Management Function (EENMF) General Description The EENMF is hosted by the EENMU. CDS for the status report and load shedding data. The for open/close orders. electrical network configuration and manages the reconfigurations as necessary. The ENMF manages the connection The ESBF sends data through the AFDX network to the EPDCs and CBPs and disconnection of the power sources in relation to their availability. The ESBF receives data through the The two CPIOMs that host the ESBF and the ELMF for overload AFDX network from: management The CDS to show the status of the electrical distribution network and EPDCs and CBPs (ENMF and EENMF) electrical parameters The Local Power Management Function (LPMF) of the SPDBs DLCS for configuration Electrical Network Management Function (ENMF) ELMF hosted in the same CPIOMs The ENMF is hosted by the ENMUs. 69 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . ELECTRICAL POWER DISTRIBUTION CENTER FUNCTIONS A350-900 ATA 24 TRAINING MANUAL PAGE . and provide secondary distribution (low current < 15A) for essential and non-essential loads. and emergency distribution to emergency loads.70 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY CIRCUIT BREAKER PANEL ARCHITECTURE CBP Cabinet Two Circuit Breaker Panels (CBP) are installed in the nose fuselage. A350-900 ATA 24 TRAINING MANUAL PAGE . CBP Core Func ons These two physically separated CBP ensure the following main core functions: Distribute 115VAC variable frequency to essential secondary loads (<15A) Distribute 28VDC to emergency loads Protect associated wires against short-circuit/overload Provide ON/OFF commutation capability to several supplied loads Provide monitoring of the protection devices . using CB and SSPC. CIRCUIT BREAKER PANEL ARCHITECTURE A350-900 ATA 24 TRAINING MANUAL PAGE .71 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . 3.…) through AFDX network. The EDMUs give interface between the EPDS and other aircraft systems (CDS. 7. The SPDBs are connected through CAN buses to the EDMUs installed in the EPDCs. PDMMF. Numbers 11. Numbers 9 and 10 are not used to make the difference between the cabin and cargo SPDBs. EPDC1 and EPDC2 supply 115VAC and 28VDC electrical power from the EPGS to the SPDBs to supply the cabin and cargo loads with an electrical power consumption of less than or equal to 15 A through AC and DC SSPCs.72 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY SECONDARY POWER DISTRIBUTION BOXES General Description Seat Power Supply Function (SPSF) The secondary power distribution system is an electronically The SPSF manages electrical power supply from the SPDBs to the related controlled platform.A350-900 ATA 24 TRAINING MANUAL PAGE . . 6. (The 12 SPDB cabinets are physically identical). 13 and 14 identify the cargo SPDBs. 4. DLCS. 7 and 8 identify the cabin SPDBs. 11 and 13 supply side 1 loads and SPDBs 2. Numbers 1. The LPMF prevents overloads and thus overheating of the feeders that supply the SPDBs from the EPDCs. ESBF. Local Power Management Function (LPMF) The LPMF is a function of the cabin and cargo secondary power distribution system. 2. 12 and 14 supply side 2 loads. It consists of 8 Secondary Power Distribution Boxes (SPDB) in the cabin and 4 SPDB in cargo area. 12. 6. 5. seats equipment in cabin. 4. providing power distribution to non-essential cabin and cargo loads (<15A). 8. 5. SPDBs 1. 3. SECONDARY POWER DISTRIBUTION BOXES A350-900 ATA 24 TRAINING MANUAL PAGE .73 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . The switch on the doorframe of door 1 is Switch GND SVCE CTL 1. Busbars 1B and 2B and the emergency network are not supplied. VFG. The loads to be supplied during the ground servicing are connected only to busbars 1A and 2A of the network. no There are two switches to supply power to the ground service loads: contactor failure). Because it is not necessary to energize the full electrical ensure connection to EP receptacle 2. One switch on the nose landing gear The ground servicing mode is deactivated when the ground servicing One switch on the doorframe of door L 1 in the cabin switches are set to OFF or power supply from a VFG or the APU-GEN is received or An EP is selected “ON” to supply the network (through the ICP When only one GPU is used. For this reason. need to go upstairs. and one on the nose landing gear). if only one EP cord is available at your gate. catering/cleaning.A350-900 ATA 24 TRAINING MANUAL PAGE . No data is shown on the cockpit panels. EP sources. configuration. refueling and lighting are supplied. There is no dedicated AC and DC network for the ground servicing Note: For convenience.g. that are not used in the ground servicing mode. The switch on the nose landing gear steering box is Switch GND SVCE CTL2. EXT power) and at least one external power is plugged and available (but EP not connected to electrical network) and No network failure (e. are connected to the 28VDC busbar DC SHED/GS1. Ground Servicing Mode Activation/Deactivation Ground servicing mode can be activated/deactivated through one of the two “GND SVCE CTL” switches (one installed on the doorframe of door 1.74 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY GROUND SERVICE CONFIGURATION General Description SVCE CTL P/B is switched in ON position and The electrical network is not powered by any source (APU-GEN. while the loads protected by circuit breakers cannot be disconnected even if they are not necessary. This allows you to energize network. only the loads that are necessary for cargo loading and for cargo the Ground Service Network 2 using GND SVC CTL2 avoiding the door operation. The electrical power supply that is necessary for the ground servicing comes from external power receptacle(s) 1 and/or 2. the loads protected by SSPCs/RCCBs stay disconnected if they are not necessary. contactor failure) or Loss of all interconnected through the System Isolation Contactors (SIC) 3 and 4. In the ground servicing mode. all the DC loads protected by circuit breakers. potable and waste water servicing. 2. The ground servicing mode is activated if at least one of the two GND .g. side 1 and side 2 of the network are “EXT” pushbutton) or Network failure (e. 75 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . GROUND SERVICE CONFIGURATION A350-900 ATA 24 TRAINING MANUAL PAGE . When the system is active.Flight interphone Cockpit ambient lighting (limited) PARK BRAKE ON light (amber) on the steering disconnect panel (installed on the nose landing gear) . The system is active in the conditions that follow: On the TOWING ON BAT section of the maintenance panel. the functions controlled by SSPCs that follow are available: Alternate braking on accumulators VHF1 . POWER P/BSW selected ON No battery 1 fault Battery 1 Status Of Charge (SOC) is sufficient (more than 20%). the SOC is shown by the CHARGE triple annunciator light of the TOWING ON BAT section of the maintenance panel.76 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY TOWING ON BATTERY CONFIGURATION General Description The towing on battery system uses only battery 1 that supplies electrical power to the 28VDC busbar DC NORM/BAT 1.A350-900 ATA 24 TRAINING MANUAL PAGE . 77 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . TOWING ON BATTERY CONFIGURATION A350-900 ATA 24 TRAINING MANUAL PAGE . overcurrent condition ground use only. the ECAM C/B page Air Data and Inertial Reference System (ADIRS) and Landing Gear The PDMI is used for the control and monitoring of the electrical protection Extension Retraction System (LGERS) to receive the Flight/Ground equipment installed in the Electrical Power Distribution Centers (EPDCs). FWS to show the C/B TRIPPED Flight Deck Effect (FDE) when a protection device is open manually for maintenance or because of an NOTE: Because the ELEC REMOTE C/B CTL pushbutton switch is for on. The PDMI has these interfaces through the AFDX network: The PDMI can be operated only on the ground through the related ELEC REMOTE C/B CTL pushbutton switch set to ON.78 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY POWER DISTRIBUTION MAINTENANCE INTERFACE General Description The status and the different symbols of the circuit breakers. SSPCs and RCCBs are shown on the HMI displays as applicable to the aircraft The Power Distribution Maintenance Interface (PDMI) is used for configuration. The circuit breakers are monitored only The Solid State Power Controllers (SSPCs) and Remote Control Circuit Breakers (RCCBs) are controlled and monitored. aircraft status in the Circuit Breaker Panels (CBPs) and in the Secondary Power Distribution Boxes (SPDBs). It is hosted on the OIS that makes it possible to interface and communicate with the different protection devices through the Secure Communication Interface (SCI). maintenance. The circuit breakers and the protection and/or switching devices have an interface with the Electrical Discrete Interface Unit (EDIU) and the Electrical Distribution Management Units (EDMUs) in each EPDC.A350-900 ATA 24 TRAINING MANUAL PAGE . The maintenance operators can get access to the PDMI through different Human Machine Interfaces (HMIs): OMT Two OIS display units and keyboards Portable Multipurpose Access Terminal (PMAT) . The PDMI contains the Power Distribution Monitoring and Maintenance Function (PDMMF). The EDMUs are the interface with the dedicated application of the PDMI through the AFDX network. it is necessary to set it to the normal position (ON legend CDS to give the data about electrical-protection equipment status on off) before the aircraft is released to flight. 79 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . POWER DISTRIBUTION MAINTENANCE INTERFACE A350-900 ATA 24 TRAINING MANUAL PAGE . A350-900 ATA 24 TRAINING MANUAL PAGE . 2 supply 28VDC to: EMER HOT BUS 1. The PDMI on battery allows the following functions: Do a check of the aircraft configuration before you energize the aircraft Safety and tag the SSPCs and RCCBs if you remove equipment The PDMI on BAT mode is available in these conditions: Aircraft on ground ELEC REMOTE C/B CTL pushbutton switch is pushed and the ON legend is on Emergency batteries 1 and 2 are available (no fault) and their Status Of Charge (SOC) is sufficient (more than 20%) To use the PDMMF and the related HMIs. It is recommended to use it during the shortest time possible and set the ELEC REMOTE C/B CTL pushbutton switch back to the OFF position immediately after the task. When the SOC becomes too low (less than 20%). the batteries automatically stop the supply to the PDMI. the 28VDC and 115VAC are necessary for the PDMI. The emergency battery 1. . you can control and monitor the protection devices with the emergency batteries 1 and 2 as power sources to the PDMI.80 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY PDMI ON BATTERY General Description On the ground. 2 busbars Battery 1 supplies the static inverter 1 which then supplies 115VAC to the INV AC 1 busbar. 2 DC PDMI 1. when no electrical power is available. NOTE: The autonomy of the PDMI on BAT is approximately 30 minutes. PDMI ON BATTERY A350-900 ATA 24 TRAINING MANUAL PAGE .81 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . 82 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL STRUCTURE NETWORK (ESN) 1 The use of carbon fibre reinforced plastic (CFRP) material requires The electrical functions are: solutions to provide electrical functions due to the low electrical conductivity of the CFRP compared to metal.A350-900 ATA 24 TRAINING MANUAL PAGE . The environment protection functions are: To contribute to lightning strike protection (direct effect and indirect effect) To discharge static electricity and prevent its accumulation To contribute to the Electro-Magnetic Compatibility (EMC) between aircraft systems . To provide current return To distribute a common voltage reference The Metallic Bonding Network (in unpressurized areas) provides: To give a current circulation path for fault currents if there is a short- circuit Lightning strikes protection Electrostatic protection Electrical a current path (bonding) Connection to the earth when the A/C is on the ground The Electrical Structural Network( in pressurized fuselage) provides: Lightning strikes protection Electrostatic protection Electrical current path (bonding) Connection to the earth when the A/C is on the ground Electrical current return signal (grounding) Provision of common point of voltage reference for all electrical components The ESN and MBN are mechanically connected together. To keep current injection in the Carbon-Fiber-Reinforced Plastic (CFRP) elements to a minimum The solutions are the Metallic Bonding Network (MBN) and the Electrical To give protection to people against dangerous voltage Structure Network (ESN). 83 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . ELECTRICAL STRUCTURE NETWORK (ESN 1) A350-900 ATA 24 TRAINING MANUAL PAGE . A350-900 ATA 24 TRAINING MANUAL PAGE .84 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY Student Notes: . ELECTRICAL STRUCTURE NETWORK (ESN) 2 A350-900 ATA 24 TRAINING MANUAL PAGE .85 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . The standard parts (raceways. This is called the Electrical Structure Network (ESN). metal frames. electrical junctions. Additionally it is used for bonding and as connection to the ground. It includes all the parts that make the airframe mechanically stable (metal skin. a metallic network is installed inside the A/C. doors. Standard Parts Standard parts let the current flow along longitudinal and circumferential pathways. .) are the link between all the parts of the ESN.). All ESN parts also contributes to the lightning protection. All functional and power current shall return to the PVR through the ESN or dedicated wire. Primary Structure The primary structure of an aircraft is the basic structure of the airframe. The PVR is located in the avionic bay and is made of metallic elements. All the AC and DC source neutral shall be connected to the PVR. maintenance floor. roller tracks. H- struts. avionics rack chassis.86 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL STRUCTURE NETWORK (ESN) 3 Electrical Structural Network (ESN) Due to the low conductivity characteristics of the CFRP. etc.A350-900 ATA 24 TRAINING MANUAL PAGE . metal crossbeams. ESN cables. seat tracks.). etc. The Point of Voltage Reference (PVR) is the power supply voltage reference. The ESN is a metallic structure used as common current return for all circuits inside the pressurized fuselage and as voltage reference for discrete signals. Secondary Structure Elements of the secondary structure are not used for the mechanical resistance of the aircraft but as supports for equipment (cabin center attachments. etc. L-brackets. 87 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . ELECTRICAL STRUCTURE NETWORK (ESN) 3 A350-900 ATA 24 TRAINING MANUAL PAGE . 88 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY Student Notes: .A350-900 ATA 24 TRAINING MANUAL PAGE . 89 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . ELECTRICAL STUCTURE NETWORK (ESN) 4 A350-900 ATA 24 TRAINING MANUAL PAGE . ESN junction braids The green identification sleeves are used for the ESN cables. sleeves or holes-label) are easy to see: Green color ESN tag The ESN parts are identified with green labels and sleeves: The green identification labels are used for the secondary structure parts raceways.90 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ESN PARTS IDENTIFICATION The items used for ESN identification (stickers. drain cables. ESN junctions . bulkhead strips. brackets.A350-900 ATA 24 TRAINING MANUAL PAGE . ESN PARTS IDENTIFICATION A350-900 ATA 24 TRAINING MANUAL PAGE .91 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . A350-900 ATA 24 TRAINING MANUAL PAGE . raceways.92 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ESN ELECTRICAL JUNCTIONS The electrical junctions are composed of the structural junctions (fasteners) and the flexible junctions (used to connect electrically the raceways to the other ESN elements). The green identification labels are used for the ESN structure parts. ESN junction braids The green identification sleeves are used for the ESN cables. drain cables. brackets. the ESN components (secondary structure parts and standard parts) are identified with green labels and sleeves. ESN junctions . There are three types of flexible junctions: Standard: composed of an assembly between cable and lug Quick: composed of an assembly between cable and quick junction Hybrid: mix between the standard junction with lug and the quick junction NOTE: To make the ESN identification and maintenance easier. ESN ELECTRICAL JUNCTIONS A350-900 ATA 24 TRAINING MANUAL PAGE .93 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY . Any ESN physical modifications have to be analyzed PREVENT INJURY TO PERSONS AND/OR DAMAGE TO THE by Airbus before their implementation. Standard parts let the current flow along longitudinal and circumferential pathways. The electrical junctions are composed of the structural junctions (fasteners) Aircraft modification and the flexible junctions (used to connect electrically the raceways to the other ESN elements). ESN cables. This ESN Electrical Load Analysis is similar to the one performed for the Prior to working on the ESN. you must de-energize the aircraft electrical electrical power generation and distribution system. circuits and insure the aircraft is correctly grounded.) are the link between all the parts of the ESN. In case of system modification or addition. For the junction lugs. Use a special current clamp for the current injection.94 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY ELECTRICAL STRUCTURE NETWORK TESTING General Description The standard parts (raceways. When you measure the voltage at the junctions. The ESN modification has to be treated with precaution. To do the tests of ESN junctions. electrical junctions.A350-900 ATA 24 TRAINING MANUAL PAGE . it is necessary to measure the contact resistance. it can be necessary to remove the blue varnish to have a good conductivity for the voltage probes. . Electrical Structure Network Measurement Unit tests are necessary for all the flexible junctions when you do ESN measurements and tests. AIRCRAFT. an electrical load analysis has to be done for WARNING: BEFORE YOU DO WORK ON ESN PARTS. Special tools are available for the ESN measurements/tests. The test procedure is related to the type of ESN junctions. apply blue varnish on the applicable surfaces. etc. After the measurement. you must use a special tool and high current values (up to 100 A). THIS WILL injection scenarios). MAKE SURE return current in order to guarantee the performance of the ESN (current THAT YOU OBEY THE ESN SAFETY PROCEDURE. ELECTRICAL STRUCTURE NETWORK TESTING A350-900 ATA 24 TRAINING MANUAL PAGE .95 1 Jan 2017 EFF– ALL FOR TRAINING PURPOSES ONLY .