How to lock a large circuit breaker?

circuit breaker panels

circuit breaker tester

For very large MCCB’s, most after-market lockout devices just aren’t big or robust enough. As the breaker grows in size, so does the on/off toggle. If you need to lock off a large circuit breaker, consider using a ‘Claw’ type interlock.

It’s important to note that interlocks and lockout are NOT competing technologies; just a different means to an end. An interlock device can be integrated into a system procedure that compells the operator to follow a defined sequence. That said, an interlock can be quite a bit more expensive.

Where process and operational safety is essential, focus on choosing the right device, rather than the cost. Here’s an image of a claw interlock being used on a large MCCB. Can only usually be applied where the breaker is ‘back of board’.

Claw interlocks available now from Total Lockout.

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