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Old 03-18-2017, 11:37 AM   #41
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sparkiez - awesome write up for troubleshooting! The only thing I'd add, would be to megger, or at least minimum ohmmeter, the wiring from the starter straight through to the motor.. That proves the integrity of the power wiring. Most times, I'd disconnect in the cubicle and megger from there out without unhooking the motor.. If there was an issue, I'd open the motor and check again to determine a feeder issue or motor...
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Old 03-18-2017, 10:30 PM   #42
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sparkiez,

Fantastic post!!! Your explanation needs to go into the modules at every school for motor courses.
The boss has decided to let it be until they are ready to commission their loop for the summer. If I get to poke around some more I will report back here.
Seriously awesome post, I envy your apprentices!
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Old 03-19-2017, 12:43 PM   #43
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sparkiez,

Fantastic post!!! Your explanation needs to go into the modules at every school for motor courses.
The boss has decided to let it be until they are ready to commission their loop for the summer. If I get to poke around some more I will report back here.
Seriously awesome post, I envy your apprentices!
I did not read sparkiez post, but will, when I have some spare time.
Seriously, are we still working on this?
An amp meter (clamp) would have narrowed this down for you.
Have you not checked the current on each leg with the motor running?
This will tell you what you want to know.

This is very common and is not always easy to find. I'm going to give you a hint. The leg that is drawing 0 (zero current) is your problem.
Then its just a matter of locating the bad contact or bad connection.
This part will be harder......LOL
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Old 03-19-2017, 12:50 PM   #44
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I did not read sparkiez post, but will, when I have some spare time.
Seriously, are we still working on this?
An amp meter (clamp) would have narrowed this down for you.
Have you not checked the current on each leg with the motor running?
This will tell you what you want to know.

This is very common and is not always easy to find. I'm going to give you a hint. The leg that is drawing 0 (zero current) is your problem.
Then its just a matter of locating the bad contact or bad connection.
This part will be harder......LOL
Even off kilter current means pure trouble. 100A; 100A; 50A -- that's one sick puppy.
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Old 03-19-2017, 03:43 PM   #45
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Even off kilter current means pure trouble. 100A; 100A; 50A -- that's one sick puppy.
Typically any more variance than 10% is a big issue.
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Old 03-20-2017, 12:40 AM   #46
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You guys are right, there were a few things left out. I specifically didn't give instructions for taking the amp readings because there is some safety concerns for me with a loaded circuit.

Also checking the wiring from the bottom of the starter to the top of the disconnect and from the disconnect to the motor, or even megging the motor from the bottom of the disconnect works quite well, but once again I have some safety concerns (I don't know his skill level).

Also, I'm an apprentice myself. I just started in the industrial sector so my first year was just distribution and troubleshooting while the next two were PLC and instrumentation / controls for the plant as I was the only guy there that could actually do that work, I kinda got the job without experience and by default.
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