ABB UniGear ZS1 - Maintenance in Busbar Compartment

86
Figure 134: View of the busbar compartment, shown without insulating covers
2 Branch conductor
3 Busbars
5 Tulip isolating contact
9 Bulkhead, removable
3
2
9
5
• Clean the surfaces:
- Remove any dry dust deposits which are not very adherent using a soft dry cloth;
- Remove any more adhering dirt with a low alkaline detergent or with ETHANOL F 25 M;
• Clean the insulating surfaces and the conductive components with ETHANOL F 25 M;
• After cleaning, rinse with clean water and dry carefully;
• Should any partial discharges occur as a consequence of the condensation phenomenon, a
temporary remedy which is often effective is application of a thin layer of silicone over the surface
involved. For a permanent remedy to this type of unusual problem, contact the ABB after-sales
assistance department.
7.3.1 Maintenance in busbar compartment
7.3.1.1 Checking of the tightening main busbars
• Make the plant you want to work on safe (follow the plant safety regulations).
• Remove the circuit-breaker from the panel where you want to work and close the earthing switch.
• Close the earthing switch relative to the main busbars.
• By accessing through the circuit-breaker compartment, remove the bulkhead 9 (Figure 2) unscrew-
ing no.7 screws M8.
• After the removal of the bulkhead from the circuit-breaker compartment, the main busbars are
visible.
• Using a dynamometric spanner, check tightness of all the screws. Refer to the table on page 40 for
the tightening values;
7.3.1.2 Visual inspection of the insulating materials
• Make the plant you want to work on safe (follow the plant safety regulations);
• Remove the circuit-breaker from panel where you want to work and close the earthing switch;
• Close the earthing switch relative to the main busbars;
• By gaining access from the circuit-breaker compartment, remove bulkhead 9, unscrewing no.7 M8
screws;
• After removal of the bulkhead from the circuit-breaker compartment, the main busbars are visible;
• Visually check that the top monoblocs 5, where the tulip isolating contact is housed, are integral and
do not show any breakages;
• Visually check that the insulating covering of the main busbars and the insulating joining cover of
the busbars are integral and do not show any breakages;