Eaton Power Circuit Breaker MDN-516

Charge the breaker mechanism springs using the charging handle or motor operator.

Close the breaker by applying rated voltage to the spring release accessory and verify closing by noting the state of the indicating flag.

Charge the breaker mechanism springs using the charging handle or motor operator.

If using the motor operator, disconnect power to prevent automatic recharging.

Check the state of the pop-out trip indicator. If it is 'out', reset it.

Use the mating line of the housing halves as a reference guide for visual inspection

Remove the arc chutes and inspect each primary contact structure for signs of wear and/or damage

Use the contact wear indicator to inspect each contact

Is the back end of any contact below the ledge?

Replace the contact assembly if any contact is below the ledge

Ensure device conditions are met

Remove all primary and secondary power for fixed mounted circuit breakers

Remove drawout circuit breakers from the cassette

Breaker Functionality Verification

Verify breaker operation by charging, closing, recharging, and opening the breaker

Mechanical Interlock Verification

Remove arc chute screws and all arc chutes from the arc chamber

Turn each arc chute upside down and visually inspect the inside

Check for erosion and sooty discoloration on the splitter plates and insulating jacket

Replace arc chute if severe signs of erosion or discoloration are found

Inspect the primary contacts for wear (Refer to Primary Contact Inspection procedure on page 59)

Check device (Fixed) position of poles

Check device (Fixed) position in cassette

Check device (Drawout) position of poles

Check device (Drawout) mechanism

Check device (Drawout) position in cassette