breaker trips

[dave_asdf]

Hey guys, quick question for you.
I've got a few 3000A 480V breakers that recently tripped on a short across all three phases. Is there any testing or maintenance on these breakers or the transformer that supplies them you would suggest before I return these breakers to service? thanks guys.

-dave

 

[Pierre C Belarge]

If you go to the NEMA website, they have information on circuit breaker maintenance that you may want to download.

www.nema.org

 

[charlie tuna]

the breaker is doing it's job by tripping and is designed to trip. most manufacturers recommend cleaning and testing them every seven years.
they clean and lubricate them and then use a d.c current source to test the setpoints and interlocks.

 

[zog]

I think you are looking for NETA, not NEMA. www.netaworld.org Many breakers require an overhaul after 2 or 3 fault interuptions (Look in the manufactures maintenance manual for exact number for your breaker).

You would want to do a Megger test, contact resistance with at least a 10A DLRO, and a primary injection trip test for all functions.

The transformer would need a TTR, PI/DAR, winding resistance, and an oil sample (DGA) if oil filled.

 

[petersonra]

Re: breaker trips

Hey guys, quick question for you.
I've got a few 3000A 480V breakers that recently tripped on a short across all three phases. Is there any testing or maintenance on these breakers or the transformer that supplies them you would suggest before I return these breakers to service? thanks guys.

-dave

my personal opinion is that testing these kind of things is not something your average electrician can do.

I would be inclined to have someone do it that does it pretty regularly.

 

[catchtwentytwo]

my personal opinion is that testing these kind of things is not something your average electrician can do. I would be inclined to have someone do it that does it pretty regularly

Amen to that. Especially with 3000 ampere breakers.

 

[dave_asdf]

Thanks for all your input guys. I agree also, i hadn't planned on doing any of the maintenance myself but i trying to get a little input before i called my breaker guy and told him what happened. you know how dealing with a vendor can be if you don't know a little about what you're talking about.

 

[zog]

I used to do breaker testing in Tampa, but have moved on. I was wondering who you are using, I know there are not many qualified shops in that area.

CBS in Lakeland may be your best bet (Ask for Christy), or go to www.netaworld.org and search for members in FL. ERS has a Ft Myers breaker shop , they do good work also.

 

[dave_asdf]

actually this equipment is in california, i'm out visiting for this startup. we already have a "breaker guy" under contract but thanks for the input. i put them down as a florida contact. it's hard to find a good tech sometimes. Thanks all for your replies.