The Importance of Proper Motor Overloads
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I pretwist and then use wire nuts. Solder pots rule.
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A little grease and its good to go.
Here its a loosing battle to have out maintenance, pump and service electricians change the o/l's when changing motors.
The answer is always the same, "It worked before" & "Its suppose to run at the service factor, that's why it's labeled".
Here its a loosing battle to have out maintenance, pump and service electricians change the o/l's when changing motors.
The answer is always the same, "It worked before" & "Its suppose to run at the service factor, that's why it's labeled".
I make all the electrons line up for their Flu shots
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FWIW, I bet it went single phase before all that happened.
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The same thing happened in an I-R screw compressor. The 60 HP must've got hot that the rotor melted in the same way. The compressor and the motor bearings didn't seize and the overloads were correct. A special OEM motor, made for IR, by Reliance. The new motor was made by Weg.This 2HP motor came into our shop for repair, and when they yanked the end-bell, this is what they found.
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That's the remains of a cast aluminum rotor. My expert opinion is I think it got a little warm. :laughing:
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I don't know enough about it to say if it's possible for an intra-rotor failure to cause that kind of heat without causing overcurrent in the stator? I'll run it by our motor gurus and see if they have any theories.
I handled the hell out of it right before lunch, and now despite washing my hands, I am eating the stinkiest sandwich ever.
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769 Posts
No.
If a motors windings are OK, but it draws high amps the bearings are bad. Probably dry.
30 bucks in new bearings and about 15 minutes in time and you have a motor that is good to go.
That is of course unless the endbells are wallowed, then its junk.
Even at a high rate of pay, that is way cheaper then a new motor. Especially if its some type of odd frame, or god forbid of German manufacture.
That 2 HP motor could run $4000.00 bucks and be 5 weeks out.
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That's a big "it depends." A skilled guy quickly putting new bearings in a small motor can still be economical, even if it's an off-the-shelf variety.
I agree that rewinding small off-the-shelf motors doesn't make sense, and it's easy for a repairs to quickly over-run the cost of a new motor.
But this is some special OEM motor and it will be completely rebuilt and rewound, and it's cost-effective because getting this particular motor new would be thousands of dollars.
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Funny you say that, I had a vegi sandwich with jalapeno bread, pepperjack cheese and extra jalapenos on it.
I figure if I gotta eat lame-ass healthy vegetables, I'm gonna make it as intense as possible.
I agree?!?!
I hope you're only eating a veggie sandwich today because you ran out of lunchmeat....
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I dont know about John, but I sure would not consider myself poor,Are you poor?
and I eat vegetable sandwiches all the time.
They are good, and good for you.
I like them on french bread, made with fresh spinach, green olives, tomato, and a lot of banana peppers, and olive oil.
Your colon will appreciate the break.
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31,030 Posts
Pfftt, it is not a sandwich if there is no meat in it.
I would be willing to bet that the windings in the rotor began shorting out, leading to heat concentrated in the rotor, not so much the stator.
Notice how the stator is burned in only a few places, not the entire winding.
Aluminum melts at about 1200º, there's no way the stator got hot enough to melt the rotor.
BTW, that looks like a 2 pole design; somewhere around 3450 RPM.
Notice how the stator is burned in only a few places, not the entire winding.
Aluminum melts at about 1200º, there's no way the stator got hot enough to melt the rotor.
BTW, that looks like a 2 pole design; somewhere around 3450 RPM.
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...I hope you're only eating a veggie sandwich today because you ran out of lunchmeat....
Are you poor?
Pfftt, it is not a sandwich if there is no meat in it.
:lol: Focus, guys!
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