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Discussion Starter · #1 ·
Sewer lift station, has 2hp motor drawing 8Amps on one leg and 27 on the other. The cable is in great shape. I used a megger and my windings were good I'm curious what else it could be?? Their is a capacitor and that's good also.
 

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MEISENBURG said:
Sewer lift station, has 2hp motor drawing 8Amps on one leg and 27 on the other. The cable is in great shape. I used a megger and my windings were good I'm curious what else it could be?? Their is a capacitor and that's good also.
Did you megger the motor directly, or from the control box? Maybe a wire is frayed somewhere, I would megger from the control box and see if it's good from there.
 

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Sewer lift station, has 2hp motor drawing 8Amps on one leg and 27 on the other. The cable is in great shape. I used a megger and my windings were good I'm curious what else it could be?? Their is a capacitor and that's good also.
2hp?8 amps? this is not even possible let alone 27amps. do you have a circuit breaker there? what's the temperature of your motor? if everything thing is ok I would change my clamp meter battery.

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What's it doing that made you troubleshoot it to start with?

Current is never lost in a system, so on a two wire feed that's working properly you've gotta have the same amount of current on both legs. If you truly have an imbalance like that, you have a winding ground-fault and that's where your extra current is going.

How'd you meg it?
 

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Discussion Starter · #5 ·
The overloads were making the starter trip out. The megger the had was an old wind up, there was two setting megg-ohm and ohm. I used ohm and it was mostly towards infinity. There was two sets of wires going to the motor i did each one maybe the megger is bad. Do you think that a fluke 179 is good enough on the ohm scale? Knowing we don't have another megger?
 

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Discussion Starter · #6 ·
The motor is down in a whole. The feeder goes to a terminal bar, to capacitors then to the starter. The starter is so old the thermals look like springs. Not really used to seeing that but. I do agree that it is a winding just wish I can see it . Everything mechanical is good so.
 

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The overloads were making the starter trip out. The megger the had was an old wind up, there was two setting megg-ohm and ohm. I used ohm and it was mostly towards infinity. There was two sets of wires going to the motor i did each one maybe the megger is bad. Do you think that a fluke 179 is good enough on the ohm scale? Knowing we don't have another megger?
You need to use the mega ohm setting.
 

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Electric motors can and do show faults only under full working
conditions ! that dont show up on a meggar test !

Dont diss-miss the notion of a faulty motor just because a digital
testing meter says " OK ".

Called intra winding short ! or intermittant fault !

Most experienced motor electricians will back up that one !
 

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The overloads were making the starter trip out. The megger the had was an old wind up, there was two setting megg-ohm and ohm. I used ohm and it was mostly towards infinity. There was two sets of wires going to the motor i did each one maybe the megger is bad. Do you think that a fluke 179 is good enough on the ohm scale? Knowing we don't have another megger?
The 179 doesn't have a megger feature, that is just a setting to allow you to show high resistance values. You need to get an actual megger that has a power supply to properly check windings. Just reading resistance isn't going to give you the right info.
 

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The 179 doesn't have a megger feature, that is just a setting to allow you to show high resistance values. You need to get an actual megger that has a power supply to properly check windings. Just reading resistance isn't going to give you the right info.
Beat me to it...
A 179 is powered by a 9VDC battery, it is not going to show you anything useful in a motor winding.

You said you had a wind up megger right? Use it on the Megohm setting. Using it on the ohm setting will make a typical insulation leak look like nothing, which is what you saw.
 

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Actually use the megger and do an insulation test and report back.

Check for a J-box inside the wet well too, those like to get filled with poo water and leave you with a big melted/corroded ball of wire, wire nuts and poo. :laughing:
 
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