DC Motor cant turn

[Leendabests]

Hi friends,

Im facing problem with DC motor at our factory which is cant turn on load or rotate very slow. We have checked all the insulation at Field coil and armature coil and they are all having good IR which is Field coil(2000 Megaohm), Armature coil(2000 MegaOhm). Carbon brush just changed new. Commutator skimmed. What else i need to check to besides that?

Highly appreciate for all the comments and opinions.

 

[Skogsgurra]

There is more to it than just insulation.

Armature and Field winding resistance? Currents and voltages in and across Windings? Measure and compare to motor nameplate.

Gunnar Englund

http://www.gke.org

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Half full - Half empty? I don't mind. It's what in it that counts.

 

[waross]

What size motor? How is it supplied? (DC motor controller?, DC motor starter?, Ward Leonard system?,)


Bill
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"Why not the best?"
Jimmy Carter

 

[Leendabests]

We have checked all the current and voltage free load, made measurement on winding resistance and insulation resistance. No abnormal value detected. The motor is 125 KW using as DC motor controller for the printing machine. The motor got excessive vibrate and high amp on load. Other motor has been swapped at the machine and it is working in good condition. What other thing that i need to consider even if the insulation resistance is ok.

 

[dArsonval]

“…The motor got excessive vibrate and high amp on load…
… excessive vibrate and high amp on load…”
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The motor has Electrically Failed.

The cause(s) of failure are numerous.

It could be the Interpoles. It could be a combination of the Interpoles, and [the] Armature.

Until a complete inspection of the apparatus takes place, no one in this forum can contribute any
meaningful / helpful information.

Photos? Send photos of your failure.

Pictures help a lot!

John

 

[racookpe1978]

What is is its speed when NOT loaded?
What does it feel like when you turn it by hand/torque wrench with no power and no load?
have to checked its bearings and clearances and vibration mount connection?
What is its load?

 

[MikeHalloran]

Printing machines are complicated, and can fail in ways that will overload any electric motor. As racookpe1978 suggested, decouple the motor and try to turn the printing machine input shaft with a big wrench.



Mike Halloran
Pembroke Pines, FL, USA

 

[flexoprinting]

Has your Tech. checked from motor back to it's source? Bad contacts maybe? I agree with Mike, check for machine resistance.

 

[dArsonval]

10 Jun 14 21:33 Post by Leendabests clearly states, “…Other motor has been swapped at the machine and it is working in good condition.”

So... The original motor "Electrically Failed".

John