Faulty MCCB Legrand DPX 1600

[lukin1977]

Dear Sirs,

We have in operation a MCCB Legrand DPX 1600 and the other day we need to cut the power of the network to do same maintenance works and after we finished the works we tried to reconnect the Breaker nut as soon as we pull up the MCCB`s handle it goes down again (not fully down)
Disconnected the mains supply to the breaker and still does the same. We also tried with supply ON and Load OFF but same thing

We took out the MCCB. I know that this MCCB has an electronic release witch I dont know what it means.

Any one can help me solve the problem?

 

[wbd]

When was the last time maintenance was done on this breaker? That is mostly part if not all of the issue. I would get it sent to a breaker repair shop for a complete overhaul.

I think that is the best and safest option as the breaker will be tested after repair/maintenance and you will have a breaker that will be trustworthy.

I hope that while you were fiddling with the breaker while the bus was energized everyone had arc rated PPE on as the risk for an arc flash was high.

 

[lukin1977]

wbd

The breaker has never been under maintenance. We send the breaker to a repair shop and they just told me that they found the problem and that it is in working conditions now

Good news

 

[dpc]

Interesting. A molded case circuit breaker is not serviceable -- at least per UL. It must be replaced.

 

[jraef]

The action that you are describing is that of it tripping (...it goes down again (not fully down)). First thing I would check is to see if, in whatever maintenance you did, someone created a short. The breaker might be doing EXACTLY what it is supposed to do!


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[davidbeach]

The mention of "electronic release" makes me wonder if it doesn't have an undervoltage release that gets control power from downstream of the breaker. If so it won't ever get closed until/unless an alternate source of control power is provided.