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Engineering

09/28/2010 10:27 PM

Why ABB make MCCB fails due to mechanical failure? Since we have replaced 5 breakers which are having same problem "Mechanism Jammed"

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#1

Re: Engineering

09/29/2010 1:56 AM

Have the first four dead ones been sent back to the factory for warranty evaluation?

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#2
In reply to #1

Re: Engineering

09/29/2010 2:59 AM

Yes, but still we didn't get any root cause analysis from the service engineer.

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#3
In reply to #2

Re: Engineering

09/29/2010 3:15 AM

Oh, maybe they don't want to talk about that?

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Guru
United States - Member - New Member Engineering Fields - Power Engineering - New Member

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#4

Re: Engineering

09/29/2010 11:55 AM

As much as I do not care for ABB products, I seriously doubt anyone "makes" a defective product on purpose or even by gross negligence. Most likely there is something about the way you are using the breakers that is not being properly communicated to them. Or they had a bad component(s) come from a supplier and are loathe to reveal it yet because it would involve a massive recall and they want to do a very very thorough research job before exposing ALL of their users to significant expense to change them out. People often think this is akin to greed, but fail to recognize that a knee-jerk over reaction to a perceived problem can actually cause MORE widespread economic damage than a low incidence failure issue that can be solved by replacing product.

If I had to guess, I'd say that your first failed unit, maybe your second, were chalked up to infancy failure rates, but after the 3rd and 4th someone is investigating it. They just may not be telling you anything prematurely.

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#5

Re: Engineering

09/30/2010 5:34 AM

We cannot tell why here because we did not receive it or not enough information is there to do any guess work.

Keep chasing the maker and supplier for an answer since the replacements were also defective.

Or at the same time that you are chasing for answer /refund etc, change make.

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#6

Re: Engineering

09/30/2010 5:46 AM

I don't know the ABB product you talk about, but from what I see lately on all kinds of electrical equipment (here in Europe), I have mixed feelings about the mechanical design of the electrical equipment. Everything has to get cheaper and cheaper, even the screws are cheap stuff.

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#7
In reply to #6

Re: Engineering

09/30/2010 7:02 AM

Sorry to say but they are outsourcing everything from the far east and not checking the quality of the final items! The Cheaper cost is not being transfered to the costomers but kept as easy profit!!

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Anonymous Poster
#8

Re: Engineering

09/30/2010 7:55 AM

Is your supplier providing conterfeit components. I know other manufactures are having that problem.

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Anonymous Poster
#9

Re: Engineering

09/30/2010 3:33 PM

Please define MCCB for me.Have worked on some ABB equipment and did have some costly problems.they were due to improper assembly.

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#10
In reply to #9

Re: Engineering

09/30/2010 3:53 PM

MCCB = Molded Case Circuit Breaker

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#11

Re: Engineering

09/30/2010 4:24 PM

It could be that the mold they use for the plastic is near the end of its usefull life and the plastic parts might be slightly out of tolerance. A few of these parts out of tolerance can stack up in such a way as to not work reliably. If your experience is part of a pattern, they certainly know all about the nature of the failure. And this means the end user will never know the exact nature of the failure becuase of litigation reasons.

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Guru
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#12

Re: Engineering

09/30/2010 5:50 PM

We use ABB breakers as our standard (~100 per years) and have had to replace many handle mechanisms the last couple years. Fortunately, they are coming up with a new series that we hope will be more rugged.

The problem in most failure have been undersized metal pins and plastic parts. Somebody went too deep into the cost cutting... While most failures happen with "rough" operators, we can certainly expect an industrial component to have enough "meat" to take a little abuse. These are expensive components. A few grams of steel and plastic shouldn't affect their bottom line.

I expect a company of this caliber to have corrected this problem in the next generation.

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#13
In reply to #12

Re: Engineering

10/01/2010 7:46 AM

Check and you might find out that they are outsourcing (producing) them in Asia/China and since they have relaxed the controls because of cost, these are made with less control on the specs. I have had many contactors made for other reputable European makers, but made in China, with contact blades undersized (metal thickness) such that after several operations, the contacts become bad and sparks because of less pressure on them...had to re-bend them in place!?

Therefore you can immagine all the trouble we are having nowadays with all the top reputable European makers of electric components, who are producing them in China but stil charge high price for sub-quality! maybe we should start to buy 100% Chinese Made components that will be better made because the blame will be back on them if not! Maybe that is the strategy of the Made In China Syndrom (??)

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