BANGLADESH POWER DEVELOPMENT BOARD TENDER ... - BPDB

11. LIGHTING AND SMALL POWER SUPPLY SYSTEM11.1 GENERAL(1) Scope of WorksThe Contractor shall design, manufacture, deliver and install power stationlighting and small power supply complete with all the accessories at the site asspecified hereinafter.(2) DetailsDetail description and drawings of all lighting fittings, distribution boards,switches, DC equipment, socket outlets, poles, glands, etc., comprising the offershall be submitted with Tender.(3) Electricity SupplySupplies for lighting distribution boards of 415 Volts 3 phase 4 wire 50 Hz shall betaken from the station auxiliary switchboard.The 125-volt DC supply required for emergency lighting services shall be obtainedfrom the batteries supplied under the Section 10. Under AC failure conditions forthe DC, emergency lighting to be installed shall be automatically switched on.11.2 DISTRIBUTION BOARDSThe distribution boards and all component parts shall be manufactured and testedin accordance with the latest IEC standard. Distribution boards shall have dustproof sheet steel, galvanised, weatherproof cases. The metal casing is to beprovided with knockouts or other approved form of cable entries, correspondingto the circuit capacity, together with a suitably screened brass earthing stud.The distribution boards shall be either double pole and neutral types as requiredand shall be equipped with means to provide over load protection to each circuit.This protection shall comprise moulded case circuit breaker.11.3 CABLESAll cabling associated with the lighting and small power socket outlets servicesshall be stranded annealed copper conductor, PVC insulated galvanised steel wireor steel tape armoured and PVC sheathed as appropriate or mineral insulatedcopper sheathed cable depending upon the service required.The Contractor shall select conductor sizes for the respective circuits to mcc thefollowing conditions:a. Minimum conductor sizes for lighting circuits shall be 2.0 sq. mm and forsocket outlets 3.5 sq. mm.b. The size shall be adequate for the current to be carried.c. The size shall be adequate to limit the voltage drop in phase and neutralGhorasal 200 MW to 300 MW Gas Turbine Peaking Power Plant Project (Vol-2 of 3)108