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Ecmweb 8487 Main Power Breaker
Ecmweb 8487 Main Power Breaker
Ecmweb 8487 Main Power Breaker
Ecmweb 8487 Main Power Breaker
Ecmweb 8487 Main Power Breaker

Electrical Troubleshooting Quiz - October 11, 2016

Oct. 11, 2016
How to prevent and repair exhaust fan breakdowns

Your crew is installing the lights in a new building that’s one of several at a manufacturing facility. The plant manager tells you the power went out in the main building and he wants a second opinion.

“It’s the main breaker. My chief electrician won’t reset it until a bunch of cables have been hi-potted, and that means bringing in temporary power and lights. From what he described, it will take at least a full day. I’ve got orders to fill. Can you just find the problem?”

After a little more discussion, the plant manager tells you, “I don’t think the breaker is bad. I’ve been here eleven years, and that thing has never given us any problems. Nobody has ever had to work on it.”

Where do you start?

Regarding the plant manager’s concern about filling orders, you don’t have any good news for him. In fact, this project will entail far more than the hi-pot testing.

What you have here is a maintenance failure. That breaker hasn’t even been lubricated in eleven years. And it operated? Most likely, the breaker is severely damaged and will have to be rebuilt or replaced.

It’s not safe to reset that breaker without first ascertaining its condition. This breaker must be tested by a person qualified to inspect and test this particular breaker. But not just that breaker must be tested.

Considering the plant’s record for maintenance, you can’t just test this one breaker and the cabling it supplies. You must treat the entire service as suspect because it has not been maintained. This way of looking at things used to be merely a “best practice” but now it is required by NFPA 70E.

It’s going to be a while before power can be restored.

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