Starter Overload Heater Failure

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ptonsparky said:
Mainly because NEMA are damned near indestructible or appear to be. I still see them operational after 50 years and changing to IEC just because one overload needs replaced is a as Cow says ‘almost sacrilegious’.

I do like the capabilities of the newer overload blocks and if there are additional reasons to change, I do.
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:thumbsup:
I would also like to add. When the starter was installed, the intent of the electrician at the time is to protect the motor from overload. When the overload relay has a dial for the setting the production gods will pressure the electrician to turn up the setting. Chances are the same weak willed electrician would also be too lazy to check out a higher rated eutectic heater from the parts crib.

Jraef said:
I’m in the loose screw camp. :dunce:

Melting alloy heater elements like those don’t have anything that “wears out” or ages. It’s just a little pot of solder, it either works or it doesn’t and if it doesn’t it’s because the solder leaked out after tripping too many times. If it were bad contacts in the starter, the top lugs would be more obviously damaged long before it would make the heaters trip. AB starters are vertical lift gravity drop out, so the heaters are ALWAYS on the bottom, but heat rises. So if the heater block itself is hot but not the upper lug, the loose connection has to be right there at the block.
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There is another possible failure mode also related to the production gods. Sometimes after a overload trip they will keep re pressing the reset button while still hot until it develops a "cold solder joint".
 
milldrone said:
There is another possible failure mode also related to the production gods. Sometimes after a overload trip they will keep re pressing the reset button while still hot until it develops a "cold solder joint".
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:thumbsup:

I'd probably swap heater positions to see if the problem moves to another pole. This will tell you if it is heater issue or not, presuming current in all three lines is about the same, which OP said they are in his case.
 
Update on Starter Overload Heater Failure

Update on Starter Overload Heater Failure

Just an update, we replaced the heaters and the A-phase heater had a distinct burnt smell compared to the others. We have not restarted the motor yet, but to plan to shortly and perform thermography. So does anybody think, it could be something else?
 
Nardie said:
Just an update, we replaced the heaters and the A-phase heater had a distinct burnt smell compared to the others. We have not restarted the motor yet, but to plan to shortly and perform thermography. So does anybody think, it could be something else?
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We have a good mix of MCC's at the plant I work at, ranging from GE & Westinghouse (from the early 1960's) to (semi modern) Cutler Hammer Advantage etc etc. So I hear yah in ... why replace the whole starter for just one overload. I've run into similar problems in the past, I've found the best tool for troubleshooting this is a low ohm meter. Rack the bucket out, and Measure each phase through the starter from the line lugs to the bottom of the heaters or motor feeder lugs. Each phase should be very close (any difference of +/- 750 micro ohms can cause a hotspot on that phase), I would suspect you'll find a greater resistance on your A phase. Once you've seen the difference you can then test with the micro ohm meter just through the circuit breaker contacts. Anything more than 500 micro ohms and you may have to service/replace the circuit breaker. There will be a higher resistance through the overload coils because well they are a heating element. You may find you just need to scrub the surface contact area anywhere there is a joint, lug, contact etc.
 
kwired said:
:thumbsup:

I'd probably swap heater positions to see if the problem moves to another pole. This will tell you if it is heater issue or not, presuming current in all three lines is about the same, which OP said they are in his case.
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Wouldn't just replacing it be cheaper rather than faffing about with the currently installed unit?
 
Faffing... not a word we use here but after looking it up, I think we should!

You (Besoeker) are probably right in terms of the bottom line cost when faffing time is monetized, but in all likelihood his management will insist on repairing it rather than replace. To use another English phrase, “penny wise, pound foolish” is very common around here.
 
Besoeker3 said:
Wouldn't just replacing it be cheaper rather than faffing about with the currently installed unit?
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If you have a replacement readily available then it could be. If you take the time and $$ to get a replacement and that still doesn't solve the problem then probably not.

My intention there was to be able to verify the overload element is what has an issue and not something else, so if it does the problem should move to the other pole if you swap them. Worst case that only cost you the time needed to make the swap, unless it is a rather unusual situation where you can't afford the load to be down - but those cases it is likely costing something every time it trips as well.
 
kwired said:
If you have a replacement readily available then it could be. If you take the time and $$ to get a replacement and that still doesn't solve the problem then probably not.

My intention there was to be able to verify the overload element is what has an issue and not something else, so if it does the problem should move to the other pole if you swap them. Worst case that only cost you the time needed to make the swap, unless it is a rather unusual situation where you can't afford the load to be down - but those cases it is likely costing something every time it trips as well.
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From our regular stockist the complete contactor and overload assembly is ex-stock, can be collected, and costs less than a fiver.
Change it!!
 
Besoeker3 said:
From our regular stockist the complete contactor and overload assembly is ex-stock, can be collected, and costs less than a fiver.
Change it!!
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OP has what I believe to be a NEMA starter - probably size 2.

Replacement overload element for current production models maybe $20 on the low end of price range, maybe $50 on the high end.

Replacement contactor and overload assembly easily $500-600 in many cases. Just checked Grainger.com and theirs is almost $1000, but I expected them to be a little higher than other sources.

I can get IEC style contactor and overload from Automation Direct for same motor for maybe $100 or even less.
 
kwired said:
Replacement contactor and overload assembly easily $500-600 in many cases. Just checked Grainger.com and theirs is almost $1000, but I expected them to be a little higher than other sources.
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Ridiculous money for a 10kW DOL starter.
 
Besoeker3 said:
Ridiculous money for a 10kW DOL starter.
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Won't say I disagree.

I can order all needed components for a complete project and get a pretty good lump sum price, but to just get one replacement starter they gouge you on price. :( You learn to throw in items needed on other projects or just plain extras of common things for your own stock whenever getting such purchase orders. That is for us poor low volume purchasers, high volume purchasers maybe get better deal even if only requesting that single size 2 starter on a single purchase order.
 
kwired said:
Won't say I disagree.

I can order all needed components for a complete project and get a pretty good lump sum price, but to just get one replacement starter they gouge you on price. :( You learn to throw in items needed on other projects or just plain extras of common things for your own stock whenever getting such purchase orders. That is for us poor low volume purchasers, high volume purchasers maybe get better deal even if only requesting that single size 2 starter on a single purchase order.
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We’ve touched on this before. I can order a whole MCC column complete with starters etc way cheaper than just one or two buckets I need.
 
ptonsparky said:
We’ve touched on this before. I can order a whole MCC column complete with starters etc way cheaper than just one or two buckets I need.
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Had project last summer, mostly 277/480 panel, breakers, and some combination starters and disconnects, all on one quote they sold it to me for about $5700. This was for items being covered in a damage claim by insurance, not all items necessarily needed replaced, but hard to get the discount on some of those items without ordering a complete assembly so I asked my salesman to just pull up same items at over the counter price on an estimate just in case insurance would ask questions - it came out to $21,000.
 
Fan Restarted

Fan Restarted

So yesterday we restarted the fan and observed no heating issues over a three hour period. The fan is still running, so I guess it was just the A-phase heater. Appreciate all the responses. :)
 
I am not a big fan of IEC starters, I had 509s that were in service for 50+ years. I prefer the 509 and the IEC overloads, as they are temp compensated and don't have to buy heaters. AB will have a IEC overload that will directly connect to the 509.
Also the AB IEC overloads (forgot the number) have a differential phase loss mechanism, so its more sensitive in a phase loss.
 
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