Looking for motor starters with adjustable thermals

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fastline

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These things are very common inside industrial control cabinets, but I find their street price to be stupid unless I find a deal. Basically these things save motors and I love them. I have saved 3P hydro pump motors due to phase imbalance, and I have also lost motors because only a simple main breaker is used and we know breakers don't protect motors!

Basically a mag contactor with adjustable thermal overloads. Either 200V or 400V class. Just love to have a 'go to' product for this. Rack mount or other.


Just for a fun story, I visited an industrial machine that I determined was blowing the thermal on the MC for a hydro pump. Small little guy and was only .1A off spec. owner said "just turn it up".... Ha, that would have been the wrong answer. I knew no one else had touched that machine and it worked for years otherwise. I determined a phase load balance issue which was corrected, and that pump was happy again. I like these starters because they can save equipment and tell me something is up. Want to use them more!
 
All your major MC mfgs offer controllers with electronic overloads.
My favorite was an AB 1232 starter 500 series contractor, fused, with electronic (IEC) overloads. I didn’t like the IEC contractors. Those 500 started are rugged, reliable and repairable. I designed a 1232X (oversized) starter that had a Micrologix 500 PLC (Ethernet), panelview, and fiber optic switch used at well sites
 
tom baker said:
All your major MC mfgs offer controllers with electronic overloads.
My favorite was an AB 1232 starter 500 series contractor, fused, with electronic (IEC) overloads. I didn’t like the IEC contractors. Those 500 started are rugged, reliable and repairable. I designed a 1232X (oversized) starter that had a Micrologix 500 PLC (Ethernet), panelview, and fiber optic switch used at well sites
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I think Allen Bradley has changed the 500 series starters to be IEC style contactors. Somehow they also meet all the nema specs apparently. They come mounted on a plate that is the same size as the old size zero starter so you can an old size zero starter with the IEC starter and they fit in the same boxes.

I prefer the iec contactors. They are smaller, more cost effective, and they work every bit as well for most applications.
 
Just adding on to what Tom said. All IEC contactors are garbage. I always found Allen Bradley to have the best full size starters. Back in the early 80's asked our A&B honest salesman who makes the best IEC contactor told me no one. At least a dozen times had pumping stations supplied with IEC contactors where pumps started & stopped every 3 to 5 minutes. Had to replace IEC contactors at least twice a year. Most of the time there is not enough room in panel for full size say NEMA 1 , 2 or 3 starters so I replaced the IEC contactors with the largest one that will fit. Circuit breakers & fuses are really in motor circuit to handle ground fault . Some times a breaker or fuse will open during locked rotor current before the starter overloads. Had bullet proof 40 year old NEMA starters still running great. I had a lot of 60 to 150 HP drives with bypass feature and all were supplied with 3 inferior IEC contactors. Could not replace contacts in any of them unlike NEMA real deal starters. Also on these drives quite often cheap IEC contactors would either make a lot of noise after powering back up and some would not pull contacts in causing problems.
 
I have Limited experience with motor starters compared to some.
Oversizing the IEC starter never hurts esp with frequent start/stop. Use the appropriate overload block. The user selectable options are great.
Yes, the NEMA contacts last longer, but my SH never stocked them. SOL when it came time for replacement and individual MS are $$$$.
 
I don't know where you get the idea IEC contactors are garbage. I have literally put tens of thousands of them in my designs over the years. I cannot recall having a single one fail in normal use. It is true that you cannot replace the contacts on them. But it is generally cheaper to replace an IEC contactor than it is to replace a contact on a NEMA starter. And usually much quicker to do so.

There are also a lot of nifty doodads you can get with them that make them a whole lot easier to use in groups.

And you cannot beat the space-saving.

It is also true that you have to think a little bit about what you're doing and maybe upsize them sometimes. But the vast majority of applications that's just not necessary.

Like anything I suppose there are differences in quality between different brands, and maybe you just got someone who misapplied them. I can't imagine why a bypass application for a VFD would ever fail since it will not close or open with a load on unless the VFD fails.
 
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petersonra said:
I don't know where you get the idea IEC contactors are garbage. I have literally put tens of thousands of them in my designs over the years. I cannot recall having a single one fail in normal use. It is true that you cannot replace the contacts on them. But it is generally cheaper to replace an IEC contactor than it is to replace a contact on a NEMA starter. And usually much quicker to do so.

There are also a lot of nifty doodads you can get with them that make them a whole lot easier to use in groups.

And you cannot beat the space-saving.

It is also true that you have to think a little bit about what you're doing and maybe upsize them sometimes. But the vast majority of applications that's just not necessary.

Like anything I suppose there are differences in quality between different brands, and maybe you just got someone who misapplied them. I can't imagine why a bypass application for a VFD would ever fail since it will not close or open with a load on unless the VFD fails.
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Agreed. In normal applications, they will likely outlast the motor.
Now, if you an application where frequent jogging or reversing is required, you need to upsize.
 
retirede said:
Agreed. In normal applications, they will likely outlast the motor.
Now, if you an application where frequent jogging or reversing is required, you need to upsize.
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The vast majority of applications don't involve frequent jogging or reversing. Most of the time you turn the motor on and leave it on for hours.

The application mentioned above where a pumping station had pumps that were routinely starting and stopping every few minutes is a horrible application in general. The pumps aren't going to like being started and stop that much, and it seems like that whole application wasn't thought out very well. Seems to me an application like that hasn't had the mechanicals thought out. There's no good reason why you would want to start a pump up every few minutes. That's just a horrible design mechanically. I would be more worried about the motor than I would the contactor though. I can upsize a contactor but starting and stopping a motor every few minutes is going to cause it to fail probably before the contactor.
 
garbo said:
Just adding on to what Tom said. All IEC contactors are garbage. I always found Allen Bradley to have the best full size starters. Back in the early 80's asked our A&B honest salesman who makes the best IEC contactor told me no one...
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I initially laughed at the ridiculousness of the underlined part. I have a number of clients with IEC roots that spec and use thousands and thousands of them without issue. But then when I saw your reference of timeline (early 80s), I thought that maybe your statement of garbage was indeed true back then. But that was 40 years ago..
 
bwat said:
I initially laughed at the ridiculousness of the underlined part. I have a number of clients with IEC roots that spec and use thousands and thousands of them without issue. But then when I saw your reference of timeline (early 80s), I thought that maybe your statement of garbage was indeed true back then. But that was 40 years ago..
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It is was not true in the 80s either. AB salesman back then wanted you to buy the expensive NEMA stuff. I don't think they even had any in their product line then.
 
petersonra said:
The vast majority of applications don't involve frequent jogging or reversing. Most of the time you turn the motor on and leave it on for hours.

The application mentioned above where a pumping station had pumps that were routinely starting and stopping every few minutes is a horrible application in general. The pumps aren't going to like being started and stop that much, and it seems like that whole application wasn't thought out very well. Seems to me an application like that hasn't had the mechanicals thought out. There's no good reason why you would want to start a pump up every few minutes. That's just a horrible design mechanically. I would be more worried about the motor than I would the contactor though. I can upsize a contactor but starting and stopping a motor every few minutes is going to cause it to fail probably before the contactor.
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I think we are in agreement. I didn’t intend to infer the opposite!
 
petersonra said:
It is was not true in the 80s either. AB salesman back then wanted you to buy the expensive NEMA stuff. I don't think they even had any in their product line then.
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A NEMA size 1starter is actually rated for about 27A. An IEC contactor rated for the same current will exhibit similar performance, life, and physical size.
People often get into trouble using IEC devices when they are sized only by the nameplate HP.
 
petersonra said:
I think Allen Bradley has changed the 500 series starters to be IEC style contactors. Somehow they also meet all the nema specs apparently. They come mounted on a plate that is the same size as the old size zero starter so you can an old size zero starter with the IEC starter and they fit in the same boxes.

I prefer the iec contactors. They are smaller, more cost effective, and they work every bit as well for most applications.
Click to expand...
That's an option but the 509 starters are not being phased out any time soon as far as I am aware.
The thing that is changing is that the eutectic melting alloy overloads that were used in the 509 series will be phased out in the next decade or so. But they were never adjustable anyway.

I've become a big proponent of solid state OL relays now. The IEC adjustable bi-metal OLs are OK, but the "phase loss" protection is kind of a misnomer. It does not actually detect a phase loss unless the motor is fully loaded. What they do is just bias the trip point to be lower if there is less current on one phase than the other two, so if the motor is fully loaded, that biasing will mean the current in the other two phases will be higher than the new trip point and trip early. But if the motor is only partially loaded to where the current on the good phases is still below that biased trip point, the OL will NOT detect the lost phase. So it's possible to still damage a motor that was running when a phase is lost. With the Solid State OL relays, they simply look at the current flowing on each phase and if any one of them is below some threshold (some are 20%, some are 30%, some are adjustable), the relay trips.
 
I actually ordered one a year or two ago. What came in was literally an IEC starter on a mounting plate to allow it to interchange with older style NEMA contactors and NEMA style heaters. If I can remember what job it was on I will see if I can get a picture.
 
The 309 is the "new" version of their NEMA starters but based on the IEC contactors, so maybe your distributor has stopped stocking the 509s, I've heard of that happening. But the 509s are still there.
www.rockwellautomation.com

NEMA Open/Enclosed Full Voltage Starters | Allen-Bradley

Our NEMA open and enclosed full voltage starters include across-the-line, reversing, and two-speed operating modes and are available up to 2250 A.
www.rockwellautomation.com www.rockwellautomation.com
 
petersonra said:
I actually ordered one a year or two ago. What came in was literally an IEC starter on a mounting plate to allow it to interchange with older style NEMA contactors and NEMA style heaters. If I can remember what job it was on I will see if I can get a picture.
Click to expand...
I retrofitted all the 509 starters with the solid state type. The new OL easily bolted up to the 509 starters
 
bwat said:
I initially laughed at the ridiculousness of the underlined part. I have a number of clients with IEC roots that spec and use thousands and thousands of them without issue. But then when I saw your reference of timeline (early 80s), I thought that maybe your statement of garbage was indeed true back then. But that was 40 years ago..
Click to expand...
Had to replace IEC contractors & starters sometimes twice a year especially on waste water pumps that should have had tanks many times larger to prevent pumps from setting & stopping 20 times a hour. Had to throw out expensive 75 & 100HP garbage IEC contractors that were not that old because you can not replace the contacts like the full size NEMA made in USA starters. Had trouble countless times with VFD drives with enclosed 2 or 3 contractors used for bypass. IEC contractors would often single phase or no pull any of the 480 volt contacts in even while measuring 115 to 122 Volts AC at coil after power was off to perform 1 to 4 times a year PM'S.We had a tech who worked on nothing but larger vacuum pumps and he had the same option concerning short lives of IEC contractors. Told me on most vacuum pump stations that had 2,3 or 4 IEC contractors he left a brand new replacement inside of cabinet to save time running to get one.
 
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