Common use of Sub stations Clause in Contracts

Sub stations. The Contractor executes maintenance as per the Eskom maintenance strategies in all overland conveyor belts substation 1,2 and 3 including OTS and Driefontein Dam substations: SYSTEM COMPONENT ACTION 24V Brds and Chargers Remove panel covers and clean boards and chargers Check all busbars, cabling and switchgear panels Check all fuse holders, clip-on terminals and connections Check that all the SCR's are operating correctly (phase balancing) Check and correct voltage& current settings Verify that alarms are received and aknowledged by an operator Measure the standing load current Measure the ripple voltage from the charger/UPS to the battery bank Perform DC integrity test when unit is within the operators control& the plant should not trip Clean board internally Check and correct alarm settings Carry out 24V DC dual supply checks (50 Amp and 16 Amp supplies) Check for voltage differences between "O" potential and MZ (non-current caring supply) Measure and normalise the ac incoming supply voltage Replace indicating lamps Record the charger voltage and current Ensure the battery charger is in float mode when taking readings Ensure the battery voltage does not drop by 10% Calibrate chargers Check, record and report all alarms to the responsible person Perform full functional test Inverter Clean inverter panel Check all connections, fuse holders and terminals Calibrate inverter charger Clean filters Check if alarm wiring is correct Check all alarms Perform full functional test Tighten and torgue the battery cell connections Batteries Check for cracks and leaks on the cells Measure voltage on each cell and record it Check connecters for corrosion Check Flaking of cells Inspect the water level and top up if necessary Check for hot spots on termination points Check battery stands for corrosion Based on routine maintenance reading perform equalise charge on every battery bank with cells out of step. Measure and record voltage on the all battery cells Perform discharge test on the 24V & 220V battery banks and record the results Electrolyte Top up the cell if below minimum ▇▇▇▇ Use demineralised was to top up Log the volume of water consumed and cell number Measure pilot cell Vlotage Measure pilot cell temperature (25 degrees C) Take specific gravity measurements (SG) on the all the cells Battery Cabinet Inspect and replace the safety equipments if need be Inspect ventilation whether is working Inspect lighting Inspect and clean the room The Contractor inspects and ensures weekly that:  the area is clean; and  lights are maintained. The Contractor, every 3 months, inspects and cleans vacuum breakers (3,3kV breakers) and when doing so, obtains a permit to work and ensures that the vacuum breaker is racked out when the front panel is removed. The Contractor:  cleans the breaker motor;  visually inspects for the appearance of moisture in the vacuum tubes; glossy silver colour for normal conditions and milky white or transparent colour indicating deterioration; and replaces it if defective;  inspects all insulated parts for cracks;  inspects current carrying components for corrosion and cleans if corroded;  tightens all connections and bolts;  inspects mechanism for free moving parts;  inspects and cleans auxiliary contacts;  inspects electrode for wear;  inspects cable connections at back of panels for security;  cleans panel, (excluding PLC panel);  visually inspects all contactors and relays for free movement.