We have had problems with our 2000A and 3000A Masterpact breakers mounted in out side boxes. Lots of blowing snow this winter is taking out the circut board from what SD has told us, and the unit will not reset. We have older style SD breakers doing the same job all winter with not a blink. The newer breakers have a lot of bells and whistels that monitor amps and voltage ect. that we are not using or monitoring, so we are not pluged into the curicut boards for that information. Is anyone else having problem with this and what have you done to fix it? I'm not confortable with replacing it with the same breaker as the down time is not acceptable.
Square D Masterpact
- Thread starter sportster
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zog
Senior Member
- Location
- Charlotte, NC
Masterpacts have had several issues lately, recalls on the disconnects and micrologic batteries. There have also been some batches of trip units without the anti-corrosive filrm on the control boards in the trip units. But none of those sound like they are related to your issue so lets get some more details.
What is the NEMA rating of the enclosure these are in?
What do you mean by circuit board? Are you talking about the trip unit? What model trip unit do you have?
They really do not make them like they used to, that goes for all the OEM's.
The more bells and whistles the more potential issues. Adding communications to this breaker was a very expensive option and was a huge waste of money if the communications are not being used.
Depending on your set up there may be some alternate options. Were these a retrofill solution or was the entire switchgear purchased new as a complete unit?
Posting nameplate info, trip unit data, photos, and the failure analysis/test report will answer a lot of questions. If you don't want to post them you can PM them to me and I can help you out.
The breaker is a Masterpact NW 20 N 2000 amp frame Cat#WL1FFV74A3SXXXXXXX with a Micrologic 6.0H on it. From what I understand the trip curcuit board is what nis holding out the reset. It is a pump up close unit. For the most part we don't have much to do with the main disconnects at our plant it is the equimpment after that we are more familular with. This equipment was installed a year ago as a compleate new service. Our last expantion 10 years ago the same setup and we have never looked back at the main breaker doing the same operation. Any information you can give would be apreciated and help in the right replacement. Anything should last more than a year at the price.
Thanks
Thanks
zog
Senior Member
- Location
- Charlotte, NC
So the breaker was in service for awhile and then tripped and you have not been able to reset it at all? Is that correct? IF this is not the case there would be other possible solutions.
There is a manual reset that needs to be depressed, I will assume that has been tried. Is the manual reset button in or out?
So there are 2 likely issues here. Either something is sending a trip signal, preventing the reset from working (By design) or the mechanical reset of the trip actuator is not properly adjusted.
Other possible causes are:
Door interlock
Racking interlock
Factory jumpers not removed during commisioning
Failed battery (Recall on these) and <20% loading
GF system not set up properly, needs to be wired right for 3 or 4 wire system during commisioning
Remote trip signal present (via the comm circuit)
Bad CCM or BCM
Bad rating plug, (Or wrong one)
Failed cradle position switch
Bad PF (ready to close) switch
UV signal present (If you have it, which being a main breaker you might)
Voltage not present on UV release
Thermal imagin signal present
Power on shunt close (XF) coil or shunt trip (MX) coil
Should be under waranty. No doubt I can repair this breaker but SQ-D should be your first place if it is under waranty.
The more information you can give about the sequence of events and what has been tested so far the more things we can eliminate.
You seem to know breakers and I apreciate your advice. Yes the breaker is on a corn drying building that runs the 100HP fans so for 10 months out of the year the only load is lighting in that area, and yes it ran last year fully to our expectations. After the snowy winter was here for a while I noticed the lights were out and found the main tripped. 4 other plants had the same problem with same breakers. We tried everything to get it back to reset with no luck. I believe SD is going to cover it under warrenty but with $$$$$ of corn in the dryer units during the fall of the year is there a more reliable breaker that would be a better choice. Doing the same thing over and expecting a differant out come bothers me.
zog
Senior Member
- Location
- Charlotte, NC
You seem to know breakers and I apreciate your advice.[/quoetr]
Breaker are my lifeThat is all we do.
When load gets less than around 20% the CT's do not power the trip unit and the battery takes over (These batteries have a recall) and eventually the battery fails causing the trip unit setting to fail to minimum pick up and delays. There is a option on these for an external power supply, do you have that option?
These things are hard to troubleshoot in a forum like this, would be easy if it were in my breaker shop but too many things to consider to diagnose this here.
Sadly no one makes them like they used to, the power breakers made in the 50's and 60's were built to last, and they have, with proper maintenence they will last forever. You don't see nuclear plants using the newer insulated case stuff on thier safety systems, they use the old reliable ones. Imagine if GM and Ford built cars to last 1,000,000 miles, what would happen to thier sales?
At this point replacing these with a different package does not make much sense for your plant, these problems can be fixed. Did anyone ever do any acceptance testing on these? You may want to consider getting an independent 3rd party testing company out there that specializes in these matters. I know good companies all over that can help you if you need a recommendation.
- Location
- Wisconsin
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- PE (Retired) - Power Systems
Actually the recall is in the past tense, I believe it was issued 2-3 years ago. But, the issue with 'lightly' loaded trip units is very real.
As standard, all NW breakers include provisions for a separate 24VDC power supply to the trip unit. I can't believe people will pay for 3000A breakers and then try to save money by not powering the trip units from an independent supply. I can't count the number of times I have gone up to an 'open' Square D, GE, or Cutler Hammer breaker and cannot get the trip history, status, or settings because the trip unit is not powered.
I'm new to this and tried to attach a photo, so be gental. Yes ZOG I would like recomendations for someone in the Des Moines Iowa area that could test and also your shop address and how to contact you for beaker repare down the road cuz the picture you panited on the new style breakers is not so bright. After I got all the snow out I believe there is a transformer mounted by the breaker and I'm guessing the takes the place of batteries.
Thanks again
Thanks again
zog
Senior Member
- Location
- Charlotte, NC
You are right, been a few years, time flies when you are having so much fun.
zog
Senior Member
- Location
- Charlotte, NC
Yeah, I can see that causing some problems. I will send you a PM with a local contact, he is one of the best around (NETA board of directors).
(Brrrr, sure don't miss that snow, MN born and raised)
Ok, what may be a silly question, but how the heck is all that snow getting INTO the gear? Is it not covered correctly, or is it indoor rated gear installed outside?
I think there are bigger issues here than a tripping breaker based on that photo.:roll:
Candidly I think the snow ingress issue MUST be solved first or you're gonna keep having this trouble.
Perhaps the breaker is actually (initially anyways) ok and doing its job as the snow may be causing a ground fault of low magnitude (which can easily become and even bigger fault given the right conditions.
I think there are bigger issues here than a tripping breaker based on that photo.:roll:
Candidly I think the snow ingress issue MUST be solved first or you're gonna keep having this trouble.
Perhaps the breaker is actually (initially anyways) ok and doing its job as the snow may be causing a ground fault of low magnitude (which can easily become and even bigger fault given the right conditions.
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jumper
Senior Member
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- 3 Hr 2 Min from Winged Horses
SD is sending some differant luvers/filters for us to install that they believe will be more resistant to snow. The cabenit has that now, but not working so good. So we get to try a new style. It's good to test others ideas in the real world right? You are right this problem needs to be solved first, but what I was after was a better breaker like the others we have setting in the same areas, same amount of snow around them and not blinking. From what I have gathered from your experiance is they have made them less dependable. If I could pick your brain on one more thing, someone has been talking about a "draw out breaker" that can be replaced in 10 min. time with a spare we could have on hand. I'm not sure what a draw out breaker is.
zog
Senior Member
- Location
- Charlotte, NC
Draw out is very common in this size, in fact I am suprised yours is not. Someone paid extra for all the communications (Which are not used) but went cheap with the bolt in? Jeez. Draw out alows you to "rack" the breaker out, only takes a few seconds, and you could have a spare to swap. I believe there is a cell conversion kit to change yours to a draw out design. You get in touch with Lynn?
ZOG Thanks for the contact informatiom. I think working with Lynn will get to the bottom of our situation and we can have system that will be more reliable. Thanks alot for your input and contact info. When our warrenty goes out you will be seeing some breakers to re-build
Thanks again
Thanks again
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