Troubleshooting quandry?

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quogueelectric said:
It doesnt seem to have a problem with startwindings amperage just run windings amperage??
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Here is the reason for my prior post. The start windings and the run windings are the same windings, just connected wye or connected delta... this is accomplished by the contactors in the control panel.

Edit to add from post on previous page: If it is a wye-delta starter, perhaps we have some bad/arc-damaged/carboned contacts in the contactors? Most likely in the contactor that creates the delta?
 
quogueelectric said:
It doesnt seem to have a problem with startwindings amperage just run windings amperage?? What brand and type of overloads are installed in the starter?? Bimetalic, eutectic solder, solid state? Wouldnt be telemechanique not sure of the spelling I think it is a french company but they are used in some square d mccs they have a built in very tight voltage imbalance tolerance and in some fringe areas of power distribution the voltage difference is enough to trip this relay.
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Non-Schieder stuff but will check later.... Looks simular though - IEC stauff...
 
crossman said:
Here is the reason for my prior post. The start windings and the run windings are the same windings, just connected wye or connected delta... this is accomplished by the contactors in the control panel.

Edit to add from post on previous page: If it is a wye-delta starter, perhaps we have some bad/arc-damaged/carboned contacts in the contactors? Most likely in the contactor that creates the delta?
Click to expand...

Was trying to get ohm readings on the load side of the contactor (all) on the motor side but the meter range was too low for them.

Thought about bad contacts too - went through them all - seem OK (Sealed no visual) - could be a motor terminal to.... (That I can't get to yet)
 
The fluke t5 only reads to 400 ohms shame on fluke. there should be 2 sets of overloads sometimes I have seen them reversed the starter is shipped with 2 sets of ols in them usually and an untrained person may not know enough to check which is start and which is run this may be why you may have experienced winding damage. Or if the ols are not suplied you are at the mercy of any village idiot to size them properly. So check the overloads for correct range or settings.
 
crossman said:
Here is the reason for my prior post. The start windings and the run windings are the same windings, just connected wye or connected delta... this is accomplished by the contactors in the control panel.

Edit to add from post on previous page: If it is a wye-delta starter, perhaps we have some bad/arc-damaged/carboned contacts in the contactors? Most likely in the contactor that creates the delta?
Click to expand...
Yes this will be the contactor with the heavier current I believe and it is possible especially in a kitchen atmosphere nightmare central.
 
e57 said:
Non-Schieder stuff but will check later.... Looks simular though - IEC stauff...
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Most of the IEC style bimetallic overload relays do have phase loss sensitivity. This means these devices will trip faster if there is a current imbalance while the device is fully loaded. The intent of this sensitivity is to take a single-phasing motor offline faster, it does not provide phase loss protection.
 
I know the feeder has been reversed (twice) - and doubt the breaker setting have been changed - so first order will be re-reversing it (twice) and putting the high leg back where it was originally. Second - checking that motor out, as well as some other work I need to do, so we'll see.....
 
Put the high leg back and re-rotated it twice.... So far, no problems - the breaker did not have individual settings for delta - just short circuit and in-rush. (damn I for got the name of that thing again... Began with an M - euro something or other) Still stinks.... The tech is gonna check the motor against spec, as the replacement is $12k - Thats right twelve thousand dollars for a motor
 
e57 said:
Put the high leg back and re-rotated it twice.... So far, no problems - the breaker did not have individual settings for delta - just short circuit and in-rush. (damn I for got the name of that thing again... Began with an M - euro something or other) Still stinks.... The tech is gonna check the motor against spec, as the replacement is $12k - Thats right twelve thousand dollars for a motor
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So it seems to be running now even with a little genie gas thing going on? How are the amperages now???
 
quogueelectric said:
So it seems to be running now even with a little genie gas thing going on? How are the amperages now???
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Simular reading on amperage - still smells rank... Hasn't tripped yet under simular loads as before - then again it is set to trip at 40a, (Short @400)and wasn't hitting it either way that I saw.... Go figure???? Thermals could be cooked?????

I'm leaving it for the time being in the hands of the techs for the machine - but still interested in it.
 
e57 said:
Simular reading on amperage - still smells rank... Hasn't tripped yet under simular loads as before - then again it is set to trip at 40a, (Short @400)and wasn't hitting it either way that I saw.... Go figure???? Thermals could be cooked?????

I'm leaving it for the time being in the hands of the techs for the machine - but still interested in it.
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Sounds like time to make the doughnuts.
 
From the numbers in your original post, I get 2.5% V imbalance and 23% current imbalance, which is clost to what I would expect for the amount of Voltage imbalance. Still haven't gotten to read the nameplate yet for the FLA? Maybe you could get the Hulk to come lift it out for you. Once you know what the FLA should be, then you can do some figuring to see if the amp readings make sense. Then either the motor is smoked, if not maybe it needs to be derated, or the voltage balance needs to be improved. Jraef posted some good data from NEMA MG-1.
 
Have you checked the line to line voltage with out the machine running? Or megged the wires? If those both pass, it sounds like a bad motor.

If it was "current imbalance from the poco", unless this is on it's own panel and possibly service, it should/would show up in other places, not just in one, I think.

If you rule out all the evidence you can, and you're still left with evidence, you have at least some proof.

Just throwin some ideas out. It sounds like this would be a bear to move, but it may be worth, if it lets you pin down any problems, one way or the other.
 
e57 said:
I think it is spelled differently but close enough...
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The correct spelling is Merlin Gerin. The correct pronunciation is similar to Mer-Lon Zer-On. MG is owned by Schneider Electric, the same people that own Square D. Over the past few years, many MG and Square D breakers have been combined into a single offering.
 
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