maxDNA

maxDNAAn Overview METSO AUTOMATION MAX CONTROLS Key Learning Overview of maxDNA control system The maxDNA Plant Automation System (PAS) is the latest version of Distributed control system developed by Metso Automation MAX Controls, US. maxDNA works with the popular operating systems Microsoft Windows 2000/XP and Windows CE, along with high-speed switched Ethernet (maxNET) communications and Distributed Processing Units (DPUs), to give an open architecture and reliable control system. The maxDNA DDCMIS follows a multi-level hierarchy. The lowest or first level interacts with the actual plant by acquiring the parameters/status, and issuing the actuating signals/commands. This is done by the I/O modules. The second level performs closed loop control and open loop control, which is accomplished through execution of atomic blocks by DPU in maxDNA. The operator console or the Operator’s Workstation (OWS), and the supervisory console or the Engineer’s Workstation (EWS), are at the third level. At the highest level, called Enterprise Management Network, engineers and managers have access to the entire system database. The system consists of the following components: • • maxNET. maxSTATIONs have Windows XP operating system while DPUs have the compact version of Windows CE installed.used to view and edit a DPU4E point database online • HealthLog -.online configuration tool for OWS General Utilities • Serverless Software Backplane (SBP) -.monitors health of DPUs in your system • BadPointReference -.unfreezes outputs after a download • MaxMergeDPUAlm -.Provides the ability to monitor the maxDNA system from a remote location by connecting into a selected workstation via a modem or LAN connection • MaxCALCS -. Distributed Processing Units providing control and data acquisition maxPAC I/O Modules interfacing with the plant I/O maxSTATIONs providing the human interface with the system maxSTORIAN for historical storage and retrieval maxLINKS for multi-protocol connectivity with external devices maxOPC for OLE (Object Linking & Embedding) data interchange between clients.offline configuration tool for EWS • maxVUE Graphical Configurator -.flags bad references in point database • DownloadFreezeCheck -.produces a merged alarm list derived from multiple DPUs .for subscription-based services on maxNET • Remote SBP -.Application development tool kit DPU4E System Software • PointBrowser -. a redundant Fast Ethernet network for communication maxDPU4E. • • • • • maxDNA software runs on popular Microsoft platforms. The attractive features of maxDNA software for the benefit of the engineer or operator are: • • • • • • High level object-oriented programming in Graphical User Interface (GUI) Wide selection of standard library functions Provision for user-defined multi-function expandability User flexibility in assigning inputs/outputs Unique address for I/O signals Service kit (Software Development Kit or SDK) The maxDNA software package can be categorized as given below: Configuration Software • maxTOOLS4E -.Package to build calculations • MaxAPPS -. maxNET detailed architecture .used to set up system time masters per domain 2. maxNET supports real-time redundancy of networks and does not wait for extensive TCP/IP timeouts before making use of alternate network channels.2 maxNET Communication network maxNET incorporates 100Mbps Fast Ethernet with Full Duplex Switches. The link between the Fast Ethernet switches is of 100 Mbps transfer rate. and links the maxSTATIONs used by operators.runs when a workstation is configured as a proxy server TimeSync -. while the links that connect maxSTATIONs and DPUs with the switches are of 10 Mbps.• • maxPROXY -. Software Backplane middleware based on subscription services and User Datagram Protocol in the network layer of the OSI model. maxNET connects all of the DPUs to each other via switches. reliable and well-integrated system. engineers and managers into a high-speed. These include storage for other processes (such as the last display and selected point for MAXVUE) as well as a set of simulation functions. maxSTORIAN. MCS Real Time Gateway (RTG): provides an interface between the Data Bus Module (DBM) and the SBP. It provides a common information interchange format that allows any application with a need. Information provided through the SBP is available to maxSTATIONs (maxVUE and maxTOOLS). 3 rotary address switches. MCS Transport Daemon (MAXT): checks healthiness of other workstations by pinging. 2 maxNET interface ports. The RTG provides immediate data. Clients ‘read’. this program is responsible for connecting clients with providers of information.3 maxDPU4E Distributed Processing Unit Features A DPU consists of a motherboard supporting the Control Processor (CPU) and Input/Output Processor (IOP).Software Backplane interface The Serverless Software Backplane© is a plug-and-play middleware environment that allows maxDNA applications to easily communicate with each other. 1 backup link port. 1 . The SBP uses subscription services where data is only transmitted when changes are detected. SBP Software Suite • • • • • maxRRS (Registration and Routing): the core of the SBP. alarm data etc. maxLINKS etc. ‘write’ and ‘subscribe’ to that information through the SBP. The DPU chassis panel contains 2 serial ports. DPUs. It is the inter-application communication protocol cum connectivity module of maxNET. The CPU is a Pentium processor with 8 MB of flash EPROM and 32/64 MB of RAM. to acquire information from any other application. Providers ‘register’ information on the SBP. trend data. maxAlarmMerge(maxAM): Support for alarm summary and lists. MaxLSS (Local Status Server): provides a number of housekeeping functions. 2. which allows objects to be executed in three different time classes . 4 IOM status LEDs. time delays.20 ms. rate-of-change. 3 hardware status LEDs. and auto-acknowledge features. Each input has a separately configurable digital filter for contact debounce. DPU state LEDs. A fully enforced object oriented design allows encapsulation of control elements to prevent inadvertent upsets during downloads and test of new control strategies.mode switch and 1 key switch. and repetitive delta alarms. 100 ms and 500 ms. Sequence of Events Each DPU can monitor up to 500 discrete inputs as a built-in Sequence-of-Events (SOE) recorder. Each data block provides a wide range of data acquisition alarm features including multi-level. These inputs are scanned 1. re-alarm. The DPU front panel contains 3 network status LEDs. reset button and takeover button. 2 serial port LEDs. Up to 6. Redundancy & Download A primary and secondary DPU are selected through configuration. adjustable hysterisis.000 event buffer.000 atomic blocks can be executed in the DPU. Comprehensive Alarming Each alarm block identifies up to 16 alarm conditions as a digital status. All alarms are . Processing Capabilities A multi-speed processing system is built into the maxDPU4E. This permits sophisticated interlocking control strategies with all other DPU functions. A distributed point management system keeps track of the object size and the total execution time for each time class. Either DPU of a pair can be designated the primary.000 times a second and state changes are time stamped with 1 ms resolution and stored in the DPU's 10. Atomic blocks can be combined into standard and custom function blocks that provide complete control and alarming for an entire plant equipment group. When a fatal diagnostic error is detected control is automatically transferred to the secondary so that it now becomes the primary. If a severe diagnostic alarm or a fatal alarm condition exists in the inactive DPU then the Take button will be ignored.time tagged by the DPU and placed in the 10. For high stability an IRIG-B clock receiver can be mounted directly on the DPU and connected via the third Ethernet port. . However. Timing maxDPU4E time stamps process alarms and events based on its internal clock. The quality code is propagated throughout the system to be included by trend and archive data. Substitute (2) and Bad (3). the takeover button on the front panel of the unit has to be pressed. if the secondary DPU is itself experiencing a severe diagnostic alarm. Manual takeover will occur only if the inactive DPU is healthy enough to assume control. Quality Coding All data within the DPU is marked with a quality code in addition to the output value. DPU Redundant Operation • Automatic Failover: Process control is automatically transferred from the primary DPU to the secondary DPU or vice versa in less than 3 ms when the first DPU experiences a severe diagnostic alarm or when the communication between the two is lost. unless the primary DPU loses power or is reset. Doubtful (1). it will refuse control. Programming Programming the DPU is done through the IEC 1131-3 toolset in maxTOOLS4E. Four quality states are identified Good (0).000-event buffer for de-queueing by the maxSTATIONs. • Manual Takeover: To manually command either DPU to assume control. The DPU clock time is periodically updated through maxNET based on the stable time source within one of the maxSTATIONs. the chassis can be split to provide both system power and loop power. high density I/O that is designed and built to withstand the harsh electrical environment found in power plants and other high current switching environments. 2. Because each module is individually isolated. Fatal Errors (DPU cannot run regardless): .Backup States The following backup states are used to decide which DPU will remain or assume control: 1. The DPUs and the I/O modules mount in an I/O chassis assembly with a backplane to provide the I/O bus connection.4 I/O system: maxPAC The maxPAC Input/Output System links the maxDNA DCS to real world process control I/O. maxPAC is a family of I/O modules and racks that offers the user space saving. . Some Errors (DPU would rather not run): • • • • 3. Addresses must be set for each I/O module using the rotary switches which permit 156 logical addresses. The I/O modules are constructed of glass epoxy multi-layer printed circuit cards with gold plated contact surfaces that mate with gold plated connectors in the backplane of the rack that supports the modules. Serious Errors (DPU will only run if necessary): • • • • 4. which provides 11V dc power for DPUs and I/O. The maxPAC I/O System uses the Model APS Power Supply Assembly. Fully Healthy or Healthy Enough (DPU ready): • • • DPU has some I/O errors below threshold Net A and/or Net B functional (outage of one for >5 min persistence) DPU active but can’t hear backup I/O errors above threshold while some IO good Net A and/or Net B functional (outage of one for more than 5 minutes) Pulse Faults Time Errors IOM Diagnostic errors Net A and Net B both non-functional Database out of date All I/O Bad DPU total failure 2. and common) 3 I/O buses 1 DPUs connected with backup cable and with common and separate bus Mixed Configuration .I/O Configuration Options There are three ways to provide for redundancy of the I/O modules and the I/O bus: i) • • • Shared 1 set of I/O modules 1 I/O bus 1 DPUs connected with backup cable and with I/O bus looped to both Shared Configuration ii) • • • Mixed 3 sets of I/O modules (primary. secondary. each with its own I/O bus and I/O modules Independent Configuration I/O Bus • • • • • • 10 microsecond transfers 8-bit parallel asynchronous I/O bus Parity checks are performed on all I/O LSI bus interface circuitry for better reliability Check-before-execute control strategy for output signals Module address verification and multiple module detection checks • Bus fault detection by automatic confirmation of input data on every module I/O signals • • • • • Normal or common mode rejection (IEEE-171.iii) • • • Independent 1 sets of I/O modules (primary & secondary) 1 I/O buses (primary & secondary) 1 DPUs connected with backup cable. ANSI c37.90) Common mode transients bypassed to chassis metal work All points optically or transformer-isolated from the I/O bus Channel-to-channel isolation allows series or parallel connections Logic state indication on the front panel for digital modules . position. of channels 16 16 16 16 16 16 10 16 2. trends . of channels 16 16 8 16 16 16 8 Part No. motors of fans/pumps. measured value. • Manual control: Actuators.List of Analog modules Part No. control modes. IOP330 IOP331 IOP331 IOP331 IOP333 IOP335 IOP350 IOP351 Description 11V input 11V input 18V input 110V input 110V input Pulse input Form C output Form A/B output Signal Type Common dc Isolated dc Common dc Isolated ac/dc Isolated ac/dc Isolated dc Relay Relay No.1V input 100ohm kit 1-10mA output Signal type Isolated Common Isolated Isolated ac/dc Common Resistors Common No.5 Workstation maxStation MMI functions The MMI part of the maxDNA DCS is expected to perform the following functions. adjusting set point • Display: Status. valves • Command & setting: Transfer control modes. IOP301 IOP301 IOP303 IOP301 IOP305 IOP306 IOP310 List of Digital modules Description I or V input 1-10mA input 3-wire RTD TC/emf input 1-1. maxOPC server is based on OPC (OLE for Process Control). fire protection. Conitel RTU. a leading industry standard which defines a method of exchanging real-time automation data among PC based clients using Microsoft operating systems. checks for changes between sample periods. The functions of maxLINKS are: • • • Configuration of services. instrument faults Record: Plant events. sootblowers. mimics. Sequence of Events Configuration: Control loops. The protocols supported include Modbus RTU.000 points. GE Mark V turbine control etc. maxOPC can either read values directly from a DPU or use maxSTORIAN as a cache data source providing higher capacity and faster performance with reduced system loading. manufacturer’s PLCs. reports.• • • • Annunciation: Plant alarms. OLE stands for Object Linking & Embedding. Helper and transport libraries maxOPC maxOPC server and the configuration tools provide a secure. Users can archive process history data to CD-ROMs (typically message prompts for download at 80% of the disk capacity). turbine control systems. operator actions Print: Logs. it is typically installed on the same workstation as the maxOPC server to reduce subscription loading to DPUs. RTUs. easily managed data exchange interface to plant and enterprise management application software that must acquire real-time information from the maxDNA plant automation system. A maxLINKS server has the capability to interface with 8 systems. . History maxSTORIAN Process History is a highly efficient and flexible data collector/compression application that acquires user-specified information on a periodic basis. when maxSTORIAN is used as the data source. water analysis. members and underlying layers (helper and transport DLLs) Response to the SBP for Read/Write/Subscribe on the configured points Core libraries (Immediate data acquisition). AB. The tool time-stamps data at the source whenever the event or process variable changes. tuning. and stores the sampled values on the 40GB RAID disk (Redundant Array of Inexpensive Disks). The user can export and import critical process data to/from external subsystems of electrical protection. vibration measuring etc. condensate polishing. which means the ability to use different file or objects in a single application through appropriate linking with their parent applications. Additionally. maxLINKS maxLINKS is an application software run on a maxSTATION providing 16-channel multi-protocol connectivity between the maxDNA system and external devices. precipitators. ash handling. and can store upto 10. Atomic Blocks are normally grouped into larger objects to encapsulate increased functionality. attributes. and their on-data-change parameters in terms of SBP delta. and custom function blocks are part of a DPMS (Distributed Point Management System). The DPMS manages its point database. This provides control over data access security and performance loading. They are software objects that encapsulate specific engineering functionality. and executes the objects composing its database. They are the building blocks of the Closed Loop as well as Open Loop Control Systems (CLCS and OLCS). among its various functions. a Microsoft Access-style database and client/server that composes a Distributed Processing Unit (DPU). an Auto/Manual toggle switch or an AND gate. Groups of atomic blocks constitute a custom function block object. read/write privileges. These HID levels can then be assigned to a particular DPU. provides master scheduling. min/max times. .Data access is configured through a maxOPC configuration server grid window and a number of OPC configuration dialog boxes that prompt the user for tag names. Key Features • • • • Provides secure OPC client read/write data access to SBP data Supports demand writes and on-data-change and polling reads Access up to 300 values when direct access to maxDPU4E is used Access up to 2000 values maxSTORIAN is used as an exclusive cache source 2. Atomic Blocks.6 Building blocks Atomic blocks form the basis of all control or logic implementation. such as a PID. Custom function blocks can be applied in hierarchical identification levels (HID levels) to form increasing levels of control system functionality. buffers. Similar to inputs except that local value is used instead of reference. they are predominantly used to monitor the atomic blocks’ execution. Values usually obtained by referencing another attribute. attrreadable attrminval etc. reference. They are predominantly used to configure the atomic block. attrwriteable. The attributes may be divided into the following categories: General Inputs Parameters Outputs Status Foundation attributes required by all atomic blocks. They are used to generate data for other atomic blocks. Values that are the result of the function or operation with which they are associated. . All attributes have subattributes like category.Attributes The data stored in an atomic block is organized as a set of attributes. Similar to outputs. description. When a reference pointer is not specified. Unoptimized subscriptions use the pointer to pick a value from a location. Attributes that are used to receive commands from the HMI that will initiate some action within the atomic blocks’ algorithm. Eg. sequence of events reporting. references to attributes of a different type.7 Configuration Tools maxDNA Configuration Tools consist of maxTOOLS and maxVUE Graphical Configurator. They can configure the modulating/binary control strategies. Reference Subscriptions All inputs have several sub-attributes to represent their data. These tools can run in any maxSTATION. Values by unoptimized subscriptions may not update every scan during periods of high DPU activity. They are the software elements used to configure. edit and maintain the Distributed Processing Units (DPU4E) in a system. the pointer by default points to the local value. which must be interpreted. the DPU database. The local (default) value and the reference pointer fields are configurable. and maxNET interface in a DPU. and sub-attributes of input attributes. .Custom Quality Methods Commands User-defined attributes The behavior of atomic blocks may be based on the Quality of its inputs. some status type attributes that are not stored. to change mode or target value. I/O card. This takes the same amount of processor time as retrieving a local value. termination interface. The following three cases apply to input references: 1. 2. Optimized subscriptions use the reference pointer to pick a value in the DPU database (local memory) eliminating the need to subscribe to the Software Backplane. alarm types and set points. 2. The working value is always retrieved by following the reference pointer. loop execution times. These would include points outside the DPMS. bus. etc. 3. Methods direct an atomic block to perform a special function. Its alarm management features are: • An alarm list with the top alarms upto 40 • Single keystroke alarm acknowledge or silence • 10.000 entry Alarm Summary display • 8. The alarm management function has to: • Prioritise Alarms with degree of importance • Filter out alarms that do not add any value to operator decision-making. important alarms may not be accorded the attention/priority they deserve. As a result.Alarm Management One major problem faced by operators is an alarm flood during emergencies.000 process alarms and 500 hardware alarms • Point and hierarchical alarm annunciator displays • Alarm defeat and restore • Automatic alarm cutouts to prevent nuisance alarms • Programmable tone for each group/ priority of alarms • Natural language queries to filter data . • Find out the actual cause of the alarm as quickly as possible • Eliminate multiple possibilities to arrive at the root cause • Validate the diagnosis with correlated parameter values • Present the operator with a prioritised set of recovery options maxVUE reports all alarms quickly and clearly. 000) • Alarm filtering by hierarchical group and/or type. System (Diagnostic) Alarms • Station Alarms – Related to maxSTATIONs or RPUs (DPU or I/O) • Network Alarms – Related to maxNET Process Alarms • Limit Alarms – For parameters falling above/ below preset values • Status Alarms – For abnormalities in process Operator Alarm Displays Alarm summary display: • Displays filtered or unfiltered alarms (max. 4.1 New control room design incorporating workstations and Large view screens enable operators view on different plant mimics from a single location. 2. 3. acknowledged and severity Alarm list: • Displays most recent acknowledged / un-acknowledged alarms • Default size is 5 alarms. 10. 4.1 Server less system with software backplane concept 3. 4. Unit networks can be kept out of interference by using gateways and firewall. customization becomes easier and additional hardware is not needed. 4.2 Application of Ethernet for industrial networking in place of proprietary protocols. 4. . operators need not move around to access control to different plant areas.4 Simple PC based applications for programming and user interface. Due to integrated approach using same platform.2 As the complete control realization like olcs.3 Application programs use windows based software.3 A small range of hardware to realize a complex control system. 3.5 Integration of complete plant data including distant offsites like coal handling plant.4 Getting data from different PLCs and other dcs if used are easily done with OPC compliance.6 As alarm and annunciation systems are software based and hence are not limited by designed number of windows. Electronic hardware. Hence it is easier to learn and customize. other than DPUS. are used only for signal acquisition and conversion to digital. switchyard are possible as plane wide networks can do this job. variety of electronic hardware is limited. clcs etc are realized using software algorithms in DPUs. New Trends / Practices 4. 3 New Concepts Covered 3. CW pump house.Alarm Types 1. 4. but configurable from 1 to 40 • Alarm filtering by HID. 6. Latest updates or patches released by Metso automation addressing any noticed problem should be obtained and system upgraded.of NTPC System knowledge will help in implementing interfaces to mechanical and electrical systems as one is aware of the design limits. Hand on training exercises can be used to make proper procedure to implement certain changes to DPUs and application software.2 In any other Deptt/section Nil 6.2 Section /’ Dept: The learning of this training can be applied to find solution to plant problems and maxDNA is finding increasing applications in BHEL supplied units.1 Self The knowledge gained in this training complements hand on working experience gained during commissioning of unit 7 Ramagundam.3 Any other Deptt. As complete logics is in the form of software.3 Company level 1. 5.5 Application of learning 5. 5.1 In Dept / section 1.. ****************** . 5. it is certain that the knowledge gained would be useful to iron out problems at commissioning stage and for following better maintenance practices. latest software including modifications done up to the backup date shall be clearly marked and stored properly. 6 Adoptable practices in NTPC 6.4 Company Level As BHEL is expected to supply and support maxDNA system for boiler and turbine controls and balance of plant were required well into the future.