The circuit breaker will be cleaned and inspected for physical damage
-
A visual inspection of the entire circuit breaker will be done specially for items such as damaged wiring, bent secondary contacts, cracked insulators, rusted frame, etc.
-
Any item found damaged will be recorded and a suitable repair or replacement identified.
The circuit breaker's contact assemblies and mechanism will be cleaned and inspected
-
The contacts will be inspected for excessive wear, burning or pitting.
-
Pivot points will be inspected for dried and/or missing lubrication.
-
The contact assemblies will be cleaned in place.
-
All silver-plated components will be inspected for wear.
-
The mechanism will be inspected for proper operation.
The circuit breakers will be lubricated with extended life lubricant
-
Where possible, all bearings and sliding surfaces will be lubricated with the appropriate extended life lubricants.
The breaker will be operated slowly to observe the motion of the mechanism while manually cranking it from the open to the close position
-
The breaker will be operated and inspected for binding in the moving components.
-
Individual electrical components will be tested as required.
-
The circuit breaker will be inspected for applicable manufacturer updates.
-
Any additional work required will be quoted separately.
Mechanical tests will be performed in accordance with the manufacturer's specifications
-
Wipe and gap measurements will be taken and adjusted as required.
-
Mechanism adjustments, such as trip latch and release latch wipes, will be completed as per manufacturer's specification.
-
Primary contact erosion indication will be checked for proper contact wipe.
-
The wipe springs will be adjusted to ensure the correct opening speed needed for a clean interruption of the fault current.
Interlocks, mechanical and electrical, will be checked, and if necessary adjusted for proper operation
Electrical tests will be performed
-
Contact resistance tests - A digital low resistance ohmmeter will be used to record the contact resistance and compare it to the manufacturer's specifications. High resistance in the contact structure can cause excessive heat in the breaker and prematurely dry out the lubrication.
-
Insulation resistance tests - A 1,000-volt megger will be used to determine the condition of the circuit breaker's insulation to the ground and across phases.
-
Functional operational tests (electrical and manual) - The breaker will be operated manually and electrically to verify proper operation.
-
Vacuum integrity test - A high potential test will be performed on each vacuum interrupter in accordance with the manufacturer's instructions.
Test data will be included as part of the final customer report
-
All test data received will be included with the circuit breaker test report. The test report will be shipped with the equipment
For More Information
Find a service center that performs Switchgear services