Siemens SINOVA - Checking the Wear on the Contacts

Inspection & Maintenance
4.4 Performing inspection
3WJ Air Circuit breakers
Operating Instructions, 12/2022, L1V30828903001-01
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4.4.10 Checking the wear on the contacts
You have to check the wear on the contacts:
• Every 12 months or after 1000 switching operations
• After serious shutdowns
Process of checking
1. Loosen the fixing screws.
2. Remove the arc chutes.
3. Close the circuit breaker.
4. Perform a visual check of the indicator for wear on the contacts of the main contact system.
If the indicator pin is no longer visible, you must replace the main contact system.