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Joined: Apr 2001
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What has your experience been with IEC style contactors and motor starters?? Mostly I'm interested in reliability.
thanks, GJ
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Joined: Nov 2000
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As long as you use them within their ratings, they're fine. You just can't abuse them like you can a NEMA device. Apparently the Europeans treat their equipment better than we do. Don
Don(resqcapt19)
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Joined: Dec 2001
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Junkie, I've never used them, but I've never heard anything "bad" about them.
Regards, Doc
The Watt Doctor Altura Cogen Channelview, TX
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Joined: Mar 2002
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Nothing but praise here. And from a designers point very slick. Just put some DIN rail down and away you go. The dial in overloads and phase loss detectors, all fit together so neat. And if your installing them the enclosures can be alot smaller and lighter. The one problem I've had is at the supply house. The ole boys that sell pipe and THHN, tubs and all, don't have a clue what Telemechanique is at all. When I come through the door with the Square D digest they scatter. I have to fill out my own order forms for Square D.
Lighting the way
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Joined: May 2001
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echoing Don's comment, be VERY careful about their ratings, if you are even approaching their max, go up, or go with NEMA. I know of at least one case where a manufacturer used them within their ratings, but at the top quadrant, after we put the fires out (literally) we changed to NEMA.
They are space savers, agreed, but again, be very cautious.
BTW, I won't discuss the incident on the forum, the manufacturer.....voluntarily.....changed the contactors. By measurement, and calculation, the IEC's fit (again, but just) but would not take a ...normal... abuse. obviously the wrong application.
cuidado, amigo
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Joined: Apr 2002
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A polite way of describing IEC motor control is: ∙ “…very materials conservative” or ∙ “…makes good use of your smaller hand tools” or ∙ “…For when you just don’t need any of that silly, overpriced reliability.”
[It takes a whole different mindset. Electrical gear is now being whored out more.]
On the ‘crank-it-up’ OL-trip settings, there’s the assistant-junior-production-manager-trainee mentality: “I don’t care what you have to do—just get me through to the end of my shift!”
[This message has been edited by Bjarney (edited 06-29-2002).]
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Joined: Aug 2001
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I don't get involved with commercial switchgear much, but I would echo some of the other comments about the IEC/DIN-mount stuff being a little liberally rated and not always as rugged as it could be. At least, that's my opinion of the versions sold here. It's certainly not as rugged as our old switchgear used to be.
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Joined: Apr 2001
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Thanks for all the input.
We have been using IEC stuff for several years with mostly good results. Our primary application is agricultural motor control.
Some of the early A-B stuff liked to smoke coils frequently. A-B has redesigned their line and no longer support the old models.
We are currently using all Telamechanique and they seem to work OK. Not as rugged as a NEMA starter but they do the job at a pretty good discount.
GJ
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Joined: Dec 2000
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"Nothing but praise here. And from a designers point very slick." Not flaming you, Joeh20, but this is where a lot of the problems arise. The fact that they fit nicely in small areas and enclosures increases the likelihood that they will be crammed into small enclosures with restricted heat dissipation properties. The dial overload settings abets the “I don’t care what you have to do—just get me through to the end of my shift!” scenario. The cost of initial installation encourages use in facilities that are trying to cut costs and may over-look quality and the results of abuse or system abnormalities, such as power sags. We have all heard stories of every part of an installation being built to the 100% minimum standards and any weakness or overuse of one component brings everything down.
Gerald Powell
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Joined: Jul 2001
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IEC contacts pass the exact same NRTL life testing (nominal 10 million no-load and 1 million full load operations) as any NEMA device. They are smaller because their terminals operate at 75C versus the NEMA 55C, and they are not designed to be repaired.
They are often misapplied because they are available in so many different ampacities. But there is nothing inherently wrong with them. For example: an Allen-Bradley NEMA size 1 contactor is rated as 27A continuous, 32A service limit, and 10HP@480V. Now you can chose an AB IEC contactor based on 10HP@480 and get a 16A device or chose a 27A device and get a 20HP contactor. The selection choice is yours, but remember a 10HP 480V motor has a NEC current of 14A, and a typical running current less than that, which means when pushed to the typical service factor of 1.15 the motor will still only draw 16.1A max.
The adjustable overload is the same concept as any NEMA bi-metallic or even the new solid-state designs. People will misadjust them, but they will also put in incorrect heaters or even jumper across them.
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