3*Solar Charge regulator and Load Controller This feature is available with The offered solution shall be integrated one unit solar Steca PT 4110 charge regulator and a load controller. The offered unit solution shall be used as a power handling device to handle the DC power from solar source for charging the battery bank and supplying the regulated -48VDC to telecommunications equipment. During the absence of solar power, the unit shall avail the regulated DC power to these telecommunications equipment from the battery source. The offered solution shall have provision of connecting two battery banks separately. The offered solution shall also have two independent load output points each having configurable cutoff voltage. 3.1* The Solar Charge Regulator and load controller shall have following characteristics and provide the functions listed below. 3.1.1 The offered solution shall have the following connection Canbe set physically. points: 1. Double pole connection point towards the output of the Solar Junction Box. 2. 2 nos. of Double pole connection point towards the input of the DC Power Distribution Board (DCPDB) each with configurable cutoff points. 3. 2 nos. of Double pole connection point towards separate battery banks. 4. Double pole connection point for emergency charging using external DC supply other than from solar. 3.1.2 A terminal panel providing connections for power and signal lines. 3.1.3 The battery charging algorithm shall be either constant Voltage PWM charging algorithm or Maximum Power Point Tracking (MPPT) charging algorithm or both. The main function of charge controller is to regulate the flow of electricity from the photovoltaic panels to the batteries. In PV systems with batteries, the batteries must be protected from overcharging and be maintained at fully charged state. 3.1.4 Solar Charge Regulator and load controller shall have hybrid DC input port. One input port shall be used for solar panel connection (compatible to connect armoured cable running from solar junction box) and another one port for charging the battery bank by external charging equipment whenever necessary. Such external charging facility shall be provided via inbuilt DC socket (the opposite socket pair shall be supplied as an integral part of the unit). 3.1.5 The offered Solar Charge Regulator and load controller shall have 2 stage configurable cutoff point output. The first output (stage I cutoff) shall be assigned for the BTS, PWM available. available. MPPT not Can be provided externally. With Two Nos of Steca PT4140 this is possible. 8. 3.2 V per cell.8.1.9 The Solar Charge Regulator and Load Controller 's charge Yes control shall be 100 % solid state. 3. as primary load having low voltage disconnect (LVD) set at .1.8. The second output(stage II cutoff) shall be assigned for the Transmission equipments MW radio.1.0. At this mode a preset maximum constant amount of current (amps) shall be fed into the battery . The Solar Charge Regulator and Load Controller shall be used to charge deep cycle maintenance free batteries. The battery voltage shall at no time exceed the voltage of 2.46 VDC (shall be adjustable).11 It must take full advantage of the solar array output and Yes charge the batteries at a maximum rate.exchange etc.3 +/.1 BULK CHARGE The Solar Charge Regulator and Load Controller shall have the Bulk Charge mode. 3. 3.10 The self consumption of the Solar Charge Regulator and Yes Load Controller shall be less than 25 mA.6 The offered Solar Charge Regulator and load controller shall In built. As the battery continues to be charged at constant voltage.1.7 The offered Solar Charge Regulator and load controller shall Provided have a connection point for positive grounding and that grounding point should have connection to all the positive terminals of Solar Charge Regulator and load controller 3.1.2 ABSORPTION CHARGE After the preset voltage is reached the Solar Charge Regulator and Load Controller shall hold the voltage constant. the voltage of the battery increases gradually. 3.8 The Solar Charge Regulator and load controller shall be able to charge the batteries in 3 stages as follows: 3.5 V per cell. the charging current decreases. As the battery is being charged up . battery bank.1. Solar Charge Regulator and Load Controller shall not charge batteries to voltages greater than 2. Yes Yes Yes Yes 3..48 VDC(shall be adjustable).1. externally also can be have sensor and sensor port to detect the temperature of provided.3 FLOAT CHARGE After the absorption Charging the Solar Charge Regulator and Load Controller shall switch to the Float charge mode and maintain the battery voltage at the float voltage setting. as secondary load having low voltage disconnect (LVD) set at . 3.1.8.1.1. Mechanical relays for charge control are not accepted.4 The Solar Charge Regulator and Load Controller shall have above three Charging Status Indicator. Optical etc. . 3. 5 User shall be able to switch the display on or off as required.13 The Solar Charge Regulator and Load Controller shall provide load voltage control circuit in order to provide load voltage constant -48 VDC at BTS sites.1.15 The Solar Charge Regulator and Load Controller shall provide load circuit cut-off device.1.17.1.1. battery voltage. The Solar Charge Regulator and Load Controller ratings shall be 1.23 The Solar Charge Regulator and Load Controller must have a remote access monitoring/controlling system inbuilt so as to integrate with centralised power OMC.17.17 The Solar Charge Regulator and Load Controller shall have alarm/displays to indicate the followings: 3.12 The Solar Charge Regulator and Load Controller shall be capable of carrying a battery charging current and also load current as per the requirement. 3.20 Under no condition during the Solar Charge Regulator and Load Controller s operation shall any reverse current flow from the battery to the array.1.21 The Solar Charge Regulator and Load Controller shall be housed in a suitable wall-mounting box.1.18 The Solar Charge Regulator and Load Controller shall have provision to extend the battery-on-discharge alarms.22 The Solar Charge Regulator and Load Controller shall be provided with surge protectors.1 Load disconnection 3. load (output) voltage.1. 3.1. 3.1.3.4 Solar array disconnection 3.17.1.1..1. 3.14 The Solar Charge Regulator and Load Controller shall disconnect/connect the solar array if the battery voltage rises above a preset value or falls below a preset value respectively. lighting protector.3 Battery on discharge.1. charging current and load current without disconnection of the load or battery. 3. The load shall not be disconnected during such control.5 times the actual requirements. 3. 3.1.16 The Solar Charge Regulator and Load Controller shall include built-in measuring instruments (digital) to measure solar array voltage. which shall operate automatically if the storage battery voltage goes down beyond preset value (manually adjustable).1. Yes Yes Yes Yes Yes Display Yes Yes Provided externally Yes . 3.17. 3.1.17. 3. All disconnect and return voltages shall be continuously adjustable. 3.1. The Bidders shall specify the preset values for both disconnect and reconnect conditions.2 Battery on charge 3.19 The Solar Charge Regulator and Load Controller shall provide an alarm output lead. and positive terminal ground. 3. adequate space between cable entry side of the regulator and cable terminating board.24 Cable entry glands shall be provided from the bottom side Externally of the regulator unit while mounted in a vertical position.28 Even different types of provided protections (lightening and surge) of proposed Solar Charge Regulator and Load Controller will be properly connected. short circuit protection.3. lightening & transient protection as well as reverse current from battery to solar protection at night.1.1. it should be replaced by the supplier at no cost. over current protection. and in case of damage due to lightening or surge will be found during the warranty period.26 The supplier shall supply the sample piece of the Solar Ok Charge Regulator and Load Controller at the time of bid submission which will be tested by the technical team of NT. If the sample meets the requirement.1. 3. 3.25 The Solar Charge Regulator and load Solar Charge Regulator Yes and Load Controller shall be provided with reverse polarity protection. 3.1.29 The offered Solar Charge Regulator and Load Controller module shall be marked in a permanent and legible manner with: The sign Property of Nepal Telecom and NT logo (to be provided during negotiation). . 3. the bid will be selected for evaluation otherwise the bid will be rejected. In order to facilitate cable entry and termination. shall be provided.1. 3. Any bid without sample piece of Solar Charge Regulator and Load Controller will be rejected.27 NT will not be responsible for the payment of sample piece if it is damaged at the time of testing.1.