SecoGear 24kV-27kV Air Insulation Switchgear
25
Major Repairs and examples
Be sure to comply with the applicable safety
regulations when carrying out repairs.
Verify the switchgear is de-energized and the safety
measures are in place.
Pay attention to the direction of the tapered washers
and the bolted connection torque should reach 86 N-m.
•
Open the main busbar compartment and check the tightening
torques for the busbar bolted connections
•
Check the main busbar and branch busbar for any dampness
or rust.
•
Check all the sidewalls for any dampness or rust.
•
Check the main busbar compartment for any unexpected
object.
•
Restore the insulation shield and the pressure flap on the top
of the panel.
•
Check the fitness of the fixed contact and the surface
condition.
•
Open the cable compartment and check the cable connection
as wells as the connectors for color distortion.
•
Check the sealing condition of through holes for the primary
and secondary cables.
•
Check the heater condition.
•
Check the breaker and cable compartment for unexpected
objects.
•
Check the secondary connections of the CTs.
•
Check the current terminals in the low voltage compartment
for the close loop of the secondary current circuit. Check
the protection relay, ammeter, energy meter, etc. on the CT
secondary are in service.
Inspection and replacement of the
main busbar
Unexpected objects in the busbar compartment, or a loose
bolted connection, may result heated joint or even phase fault.
The procedure to change the main busbar is as follow;
•
Remove the rear covers on the busbar compartment, as well
as the same on the adjacent panels. Now the busbar is visible.
(see figure 6/1)
Figure 6/1: Busbar after opening the rear cover
•
Remove the pressure flap on the busbar compartment
•
Remove the busbar insulation shield
•
Remove the connection bolt on the main bar and branch
busbar
•
Remove the busbar from the busbar compartment
•
Install the new main busbar and fasten the joints
•
Cover the busbar joints with insulation shield
•
Reassemble the pressure flaps and rear cover panels for the
busbar compartment
