Best Motor Starting Contactor/Starter 4

[foxhoundme]

Who has the best motor starting contactor/starter? I am in the market for a reliable electromechanical motor starter rated at 480V with 22Amps. I researched the following manufacturers such as Square D Company, Allen Bradley, Cutler Hammer, Siemens and General Electric. Can someone provide their best argument for either manufacturer's starter product?

 

[busbar]

Significant factors are local track record, spare-parts availability, and real cost of production downtime. A big issue is NEMA- versus IEC-grade devices

I prefer vertical dropout devices with eutectic-alloy overload elements…like AB Bulletin 509, while not caring for GE, J-Clark or Westinghouse NEMA versions. In an earlier decade replaced a lot of IEC stuff with NEMA. But everyone has opinions.

 

[advidana]

Generally, I like GE because they do not change part very often. They still use some components that were design in the 40's.

Allen Bradey has alway been consider the cadilac because of price and quality. But I have use all of the about for 40 years and they all will give you long excellent service.

I used to like square D because of thier thick enclosure, but twenty year ago they followed the herd and have the same thickness enclosures as all the rest.

I found it is best to go to the local representative brand that gives you the best service and prices in your area. This is real important if you need spare parts or technical information.

 

[pablo02]

In my opinion, these are like any other piece of equipment -- you weigh the price, the vendor service, the ability to meet delivery schedules, past experience, options and ancilliary equipment, etc...

and the outcome will probably vary from location to location, from vendor to vendor...

in my experience, vendor support and expertise has always come to the front when dealing with any major equipment issues.. (I have used all of the reference equipment mfg,. and they, the equipment, each has strong points and weak points)

 

[peebee]

I generally agree with all above posts.

NEMA is heavier-duty than IEC. I'd recommend in general to stay away from IEC, with one exception: IEC devices are physically smaller than NEMA, so if space is at a real premium, IEC can sometimes save the day. Otherwise stick with NEMA.

Allen-Bradley is number 1 in my book, but any of the major manufacturers should be just fine.

 

[GGOSS]

Hello foxhoundme,

I generally agree with all of the above. The quality and reliability of motor starters from any of the leading manufacturers is much of a muchness these days. In fact, much of it is simply brand labelled!

I don't dispute the argument that Nema products are great however subject to your loacation they may be difficult to obtain. IEC products seem to be more readillty available in most parts of the globe (other than the states) and although the perception is that Nema contactors are 'more heavy duty' IEC specifications for contactor electrical and mechanical life runs into several million operation.

Regards,
GGOSS

 

[afterhrs]

Foxhoundme,
NEMA = Allen Bradley, Bulletin 509 series.
IEC = Siemans. Sirius series

Here are some factors I take into account for determining
IEC vs. NEMA in the order of precedence.
1) enviroment is the most important in my opinion.
NEMA= hot , oily, and dirty area, like a large
stamping press or forging machine.
Nema definiteley stands up to heat and oil
better.
IEC = lighter manufaturing, like a packaging
or box machine for finished product.

2) Mechanical stucture, your electrical
components should match the
mechanical design
NEMA= heavy duty
IEC= lighter duty

3) Length of service, how long will you be using this
machine at your facility( some will argue this
should be the first priority). Be careful with
this one, product demand is always changing
NEMA= +7 yrs

IEC = -7 yrs

One more thing to consider when using IEC components, ALWAYS up size the size of the contactor by about a third. For a 10 HP motor, I would use an IEC contactor rated at no less than 15 HP

The Siemans manual is not the easiest to use, but the product makes up for the slight hassle. I thought it was just me until SCOTTYUK pointed out he felt the same way.

Good luck,
Afterhrs

 

[PUMPDESIGNER]

OK, OK, I'll stick my neck out.
NEMA is great stuff, heavy, durable, lasts forever.
But I really like the phrase "suitable for application".
I like that phrase if a technically adept and diligent person, subject to abuse by the weak and undisciplined however.

If a contactor is in very light duty application, not many starts per day and starts are not too close together, and if you want built in phase loss protection without added expense and maintenance headaches of phase monitors, then IEC is great stuff. I know this because our applications (correctly controlled centrifugal pumps)are perfect for IEC. If we have a jockey that may get started frequently we just upsize the IEC contactor.

Our viewpoint is that the incredibly high price of the NEMA has to be justified. If both NEMA and IEC are going to last 20 years no problem based on the application, use IEC.

PUMPDESIGNER

 

[peebee]

From the Cutler Hammer 2003 Consulting Guide:

Contactor Performance
IEC Type:
Electrical life - 1 million AC3 operations; 30,000 AC4 operations when tested per IEC recommendations
NEMA Type:
Electrical life typically 2.5 to 4 times higher than equivalently rated IEC device on the same test.

Fault Withstandability
IEC Type:
Typically designed for use with fast acting, current limiting fuses.
NEMA Type:
Designed for use with common domestic fuses and circuit breakers.

 

[dpc]

To get back to the original question, I suspect you will find advocates for all of the major manufacturers you mentioned.

For better or worse, low voltage MCCs are something of a commodity product in the US. For new construction, they are often provided by the contractor as part of overall construction project. As long as NEMA and UL requirements are met, they are often viewed as equivalents and purchased based on price/delivery.

The choice may depend on existing equipment, spare parts and how you use MCCs (which are flexible in application).

 

[PUMPDESIGNER]

dpc - Your summation is close, perhaps even very accurate. However just a note. We are seeing contactors (mostly IEC) come into the market that are totally unacceptable in quality. Our dealers send us samples of equipment they are replacing with our equipment just so that we can see what the competition is doing. I have never heard of the brands we are seeing. Often we get the failed component because the dealer or equipment owner was stunned by the very short life and how really cheezy the equipment was. So beware of things and do not approve or sign off on anything you do not know at least something about.

PUMPDESIGNER

 

[GGOSS]

Hello All,

Without wanting to offen anybody here, I get the impression that some may be speaking form un-informed or ill-informed positions.

First and foremost I should mention that I agree with many of the comments made re Nema contactors being more suitable for 'heavy duty' or even 'dirty' environments.

However if we are to work with the figures of electrical life quoted by peebee (they are typical for most recognised IEC brands) and assume a typical application of say 5 starts/hour, 8 hours/day, 5 days/week, 50 weeks/year (assumed 2 week shut-down) the IEC contactor will last 100 years ie and folks that's a hell of a lot longer than most reading this will survive.

Also worth noting is the fact that most IEC contactors have a mechanical life rating of typically 10,000,000 operations. Therefore it should not unreasonable to assume that if the contactor is not being used to its rated amps and/or temperature then its electrical life will be somewhere between 1M & 10M operations, defined by given service life curves.

Pumpdesigner raises the the very important issue of brand recognition and I firmly believe has a direct relationship with quality. To that end I want to provide a practical example of some tests conducted several years ago.

I was asked to conduct a mechanical life test on 2 IEC contactors of different manufacture. One of known high quality marketed by our company, the other of asian origin and much more economical. I proceeded to mount both onto a piece of din-rail fixed to a solid structure above my work bench. The coil to each contactor was powered via the contacts of a single 'cyclic' timer programmed for 1 second on 2 seconds off. Needless to say the timer would repeat that operation until power was removed from its coil. Below the contactors (on my bench) I placed 2 large sheets of white butcher paper. After about 3 hours of operation the sheet of paper below the more economical contactor was covered in fine dust like fragments of plastic evidently comming away from the inside body of that contactor. After about 5 hours some larger fragments (pin head size) were noted and contactor began to malfunction, occassionaly jamming up. Within the next hour, that contactor siezed up altogether. Without a word of a lie, the sheet of paper below the IEC contactor was still as it was when first placed there (free of any fragments) and the contacotr continued to operate faultlessly for several more hours before the test/comparison was aborted. My point here is that "you get what you pay for".

Referring back to the typical application example given above, as I haven't been around for 100 years (although it feels like that sometimes) I can say without any hesitation that I am aware of several more arduous IEC contactor installations that have been performing faultlesly since before many of the apprentices that also work here were concieved.

In closing, if I can buy a qualtiy IEC contactor for 1/3 the price of an equivelant Nema product and save space in my panel, why wouldn't I do so based on the above?

Regards,
GGOSS

 

[peebee]

GGOSS -- you're missing the point. The point isn't the lifetime of the contactor.

Let's say the average life is 100 years for an IEC contactor, and 300 years for a NEMA. That equates to 0.01 failures per year for IEC, and 0.00333 failures per year for NEMA.

And lets say my plant has 1000 contactors.

If I did this with all IEC, I'd expect to have 0.01 x 1000 = 10 contactor failures per year. With NEMA, I'd expect to have only 3.3 failures per year.

The use of NEMA, therefore, increases the reliability of the plant, decreases downtime, and decreases maintenance costs.

 

[PUMPDESIGNER]

peebee - You are correct in your analyses except for one point. Add in the phase/voltage monitor and all the problems those components cause in maintenance and the final result can come out favoring IEC.

We use the most suitable based on project location, power quality, and intended use.

If you add in the fact that some locations have serious transient problems that damage phase/voltage monitors you might find the situation intolerable with NEMA and phase monitors.

What really is hard to get a hold on is the actual working out over time with hard data. What I have is experience, but that does no one any good except me, I cannot expect others to just accept my experience, undocumented as it is.

I have had experiences with NEMA that forced us to look hard and and start using IEC contactors.

PUMPDESIGNER

 

[peebee]

PD --

Phase/voltage monitor? I'm not quite following you, I don't understand what you're referring to. Are you talking about an electronic relay?

Most starters I deal with are pretty straightforward DOL FVNR starters, with a breaker or fuse, contactor, overload, control transformer, and not much else (except for the control circuit). Sometimes soft starters or VFD's. No "phase/voltage monitor". . . .

Please describe what you mean by this. Also, it's not clear to me what the difference between the IEC & NEMA applications would be with the monitor, why IEC would be favored, although maybe your description will make that clear.

It's very interesting to me that you state you have applications that favor NEMA over IEC, the ONLY advantages I've ever heard of for IEC are cost and space, never durability. Please expand on this.

 

[PUMPDESIGNER]

Phase monitor protects motors from "single phasing', when one of the three phases is lost. NEMA contactors will fry a motor if a phase is lost, IEC contactors will turn off when a phase is lost.
Therefore, if we use a NEMA contactor, we also have to provide phase monitor which is usually another piece of equipment.
We would like to use digital voltage/phase monitor built into the NEMA Contactor. Example would be Westinghouse Advantage Contactor/Starter.
By the way, does anyone have experience with these? Are they any good?

PUMPDESIGNER

 

[peebee]

Interesting, I never knew IEC contactors had that functionality built into them. Do you know how they achieve that? . . . Strange -- The Sq-D Digest and CH Consulting Application Guide make no mention of this -- can you verify? Are you talking about standard electromechanical contactors, or some kind of new-fangled electronic contactor?

I've had arguements before with people regarding whether or not an overload heater would protect a motor agains single-phasing. My position is that it will not, that a separate relay is required for that protection (at least, on a NEMA contactor. . .). Not to get too far off the subject, but any thoughts on that?

Regarding the Westinghouse starter -- sorry, no experience with that. I've always gone to Multilin for any motor that demanded anything beyond basic protection. Why Multilin? Well, mostly because that's what everyone else seemed to use.

 

[PUMPDESIGNER]

You are correct about NEMA contactors not protecting against single phasing.

I have not investigated IEC Standards, so I cannot give useful information about that. However, I have never seen an IEC contactor that did not have phase unbalance/loss protection. I would sure like it if someone who has the IEC codes would comment on this topic because I am guessing that the phase loss feature is an IEC requirement.

Anyway, here is how it works on Square D, Sprecher-Shuh, and I suspect on others also.

There are two trip curves for the bi-metal strips, one normal overload, and one very fast for phase loss.

All 3 phases activate a magentic coil that holds a bar in alignment. When bar is aligned the bimetals have a standard trip curve associated with their function. If a phase is lost, or if phases become unbalanced the bar tilts and forces the bimetals to trip very fast, about 5 seconds or less by my experience and testing in our shop.

What is Multilin?



PUMPDESIGNER

 

[PUMPDESIGNER]

I found enough time to get some tech info for you peebee.

At Sprecher-Schuh follow this link:

http://www.ssusa.cc/pages/mainpg/prodmainall.html

At Allen Bradley follow this link:

http://www.ab.com/industrialcontrols/products/iec_motor_control/overload_relays/E1.html

PUMPDESIGNER

 

[jbartos]

Suggestion: It appears that the starters have not been discussed, as used by industries, that much yet. For example, the nuclear industry requires Class 1E certification for starters to be applied to nuclear safety systems. There ware very few manufacturers who offer the Class 1E certificate with their starters.
General Electric Co. has their starters often associated with their major product "Boiling Water Reactor (BWR)" Nuclear Power Plant (NPP). Westinghouse Electric had their starters associated with "Pressurized Water Reactor (PWR)" NPPs.
Westinghouse Starters appear on the Suspect Components List; visit

http://twilight.saic.com/qawg/scitrend/sci798/APPENDIX B.htm

the list
Allen-Bradley has traditionally been linked to manufacturers or actually made big by manufacturers (i.e. manufacturers' sweetheart).
Siemens has many starters in the textile industry, and IEC in the nuclear industry (Siemens Automation and Russian nuclear reactors are procured by Chinese).
ABB Starters appear to be mainly 400V and 50Hz.