Checking The Wear On The Contacts - Siemens SINOVA Manual

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.
3WJ Air Circuit breakers
Operating Instructions, 12/2022, L1V30828903001-01
Inspection & Maintenance
4.4 Performing inspection
177