Dirty Ole Circuit Breaker

[xguard]

Working at one of our facilities that was built in the 1960's. The photos are of the service disconnect, unit mounted 225 amp breaker located outdoors. System voltage is 240/120 three phase.

Just curious what you would do if asked to re-use this breaker, i.e. replace the feeder. I typically call to replace equipment in this condition when our project is required to tie into it, maybe I'm being too conservative. This is because I've heard of some of our old breakers cracking when trying to break the lugs loose and also I've assumed the wire insulation may fail if it's disturbed. What has been your experience in these situations?

I've noticed that electrical equipment installed indoors, especially in conditioned spaces, seems to last much longer. Living in Louisiana with the head, humidity and bugs really takes a toll on everything.

A couple notes:
They used 3/0 for some reason when they spliced in a manual transfer switch.
Noticed one phase conductor is smaller than the other two, assuming the high leg but I didn't check the voltage.

 

[ptonsparky]

I would expect it to fail at some point in the process of removal and reconnect.


(Small hammer helps.)

 

[LarryFine]

I'm cheap frugal, and I wouldn't re-use it if I didn't have to.

 

[Little Bill]

I've never had much luck breaking the lug screws loose on old, corroded ones like that. I would replace the whole disconnect.

 

[david]

Not that it matters, could be another 120/ 240 corner ground 3 ph.

The taps on bottom of 225 amp breaker, the solid grounding electrode conductor same lug as the grounded conductor.

When you say your project is to tie into it, almost sounds temporary use.

If the voltage works for your project and it is in fact temp use, I might try and clean it up and use it, anything permanent I would replace it.

Are you in a position to make those decisions or can you only make a recommendation?

 

[jim dungar]

Not that it matters, could be another 120/ 240 corner ground 3 ph.

No.
It could be either a 240V corner grounded delta, or a 240/120V center tapped delta, not both.

 

[david]

No.
It could be either a 240V corner grounded delta, or a 240/120V center tapped delta, not both.

True, the smaller conductor on B phase, with the grounded conductor being full size seems odd.

Here when the utility supplies 120/ 240 three phase they provide a bigger can for the 120 volt grouped with two smaller cans to make up the three phase

 

[Fred B]

This looks like a definite replace.
It also looks like it had been possible submerged at one point, If so it should have already been replaced. Seeing the gravel on the breaker and in the enclosure as well as the mud look on the breaker face would point to that potential. This looks to have been a NEMA 3, was the dead front in place? There is a lot of gravel inside.

 

[Little Bill]

This looks like a definite replace.
It also looks like it had been possible submerged at one point, If so it should have already been replaced. Seeing the gravel on the breaker and in the enclosure as well as the mud look on the breaker face would point to that potential. This looks to have been a NEMA 3, was the dead front in place? There is a lot of gravel inside.

If you zoom in on the first pic you can see there are splices in there. The bottom right splice looks like it may have shorted against the side of the cabinet just to the right of the KO. Can't tell for sure. Regardless, that whole disconnect needs to be replaced.

 

[xguard]

This looks like a definite replace.
It also looks like it had been possible submerged at one point, If so it should have already been replaced. Seeing the gravel on the breaker and in the enclosure as well as the mud look on the breaker face would point to that potential. This looks to have been a NEMA 3, was the dead front in place? There is a lot of gravel inside.

I think it was missing on this one.

 

[xguard]

Not that it matters, could be another 120/ 240 corner ground 3 ph.

The taps on bottom of 225 amp breaker, the solid grounding electrode conductor same lug as the grounded conductor.

When you say your project is to tie into it, almost sounds temporary use.

If the voltage works for your project and it is in fact temp use, I might try and clean it up and use it, anything permanent I would replace it.

Are you in a position to make those decisions or can you only make a recommendation?

I can make the recommendation.

 

[xguard]

True, the smaller conductor on B phase, with the grounded conductor being full size seems odd.

Here when the utility supplies 120/ 240 three phase they provide a bigger can for the 120 volt grouped with two smaller cans to make up the three phase

This one has two transformers on a pole, one larger than the other.

 

[electrofelon]

I agree with Tom, it would be real shame if despite your very best efforts, the breaker was accidentally and unavoidably damaged while trying to get it out (wink wink).

 

[LarryFine]

This one has two transformers on a pole, one larger than the other.

Sounds like a high-leg open delta.

 

[Jraef]

Given that this is 3 phase, we can assume it is a commercial/industrial installation and as such, will require an Arc Flash label. Requirements for that include that any interrupting device be within original factory specifications and have documentation showing proper maintenance. This would never pass muster on that.