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Inspect busbar chamber, unit compartments and cable alleys. Remove tools, conductor strands and any other material lying loose.
Use vacuum cleaner to remove dust, small particles…. Do not use air hoses, which may contain oil, moisture….
Wipe the interior, particularly the insulation, using a clean cloth. Do not use cotton waste.
Check all power and control circuit connections at terminal blocks, cable terminals, switch terminals, contactor terminals and busbolts for tightness. This is MOST IMPORTANT, especially after long periods of storage.
Plug all unused holes and openings, including those for cable entries.
In case flush mounting meters and relays are packed separately, mount these on the respective cutouts and connect them. Refer to the GA/schematic diagrams and terminal chart before connecting the meters and relays.
Check alignment of operating handles for all switches and MCCBs.
While despatching the switchboard, secondaries of current transformers are shorted. Remove these shortings while connecting relays/meters.
Check operation of ACB and associated control circuit in accordance with the relevant scheme drawing.
Check all timers for proper time operation. Check that fuses are fitted in main and auxiliary circuit and that ratings are appropriate for the circuit.
Check the setting of overload relays and other protection relays. Observe proper co-ordination and check the adequacy of the fuses. During commissioning checks. Set the overload relay to the minimum value. Setting of supervision relays should be as per setting chart supplied by L&T.
Close all access plates, doors and openings before the MCC is energised.
Do not operate any power equipment with doors open unless it is disconnected from the main supply.
Ensure that wires are not hanging loose. Anchor them firmly. Preferably with plastic clamps.
Temporary connections made during testing should be removed.
A thorough check of control and protection scheme is essential before commissioning.
Ensure that all outgoing switches are in the OFF position before energising the bus.
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