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AC Motor is Humming, Vibrating

AC Motor is Humming, Vibrating

AC Motor is Humming, Vibrating

(OP)
Hi All,

I'm trying to figure out why the ac motor that I'm working on is giving a humming sound, vibrations when I turn ON the power switch. I have to give it a kick or a pushing turn to help then it runs fine. When I turn the switch to OFF position and when it stops spinning, I can hear the click like locking or braking the rotor, I think.  Please advice and give me some tips to make this motor running again when the switch is turned ON. Thanks in advance! Have a nice day!    

RE: AC Motor is Humming, Vibrating

The click is the centrifugal starting switch mechanism. From your symtoms;
1> Your switch is not making contact when it should due to dirt or corrosion.
2> Your starting winding is burned out.
3> Your starting capacitor (if you have one) is faulty or disconnected.
4> You have a wire broken or disconnected.
5> More than one of the above faults.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: AC Motor is Humming, Vibrating

(OP)
Thanks for the tips.
I checked the switch when turn ON, yes there's current.
Dissembled the motor and cleaned inside. Yes I see some corrosions. I used air gun to blow it out. Put back everything, still the same results. Humming and vibrating.
I still hear the click  

Do you know the place or links that I can order the motor parts like centrifugal starting switch, starting winding, starting capacitor, etc.
By the way, this motor has no brushes



The label on the motor is A.O Smith AC Motor
serial# S48E3     SER 2106
H/P 1/8           TYPE   S
V  115            PH   1
A  2.5            SFA
HZ  60            AMB 40 DEG C
TIME   CONT       CODE  U
FR48N             INS   B
HSG    OPEN
Thermally protected  TYPE  M

EL2004V1




Thanks,
eceg

RE: AC Motor is Humming, Vibrating

(OP)
I took them apart, cleaned inside housing using electrical contact cleaners, sand the all electrical contacts, checked all connections. Put back everything, power it up, voila......this time it spins as soon as I turn ON the switch. :)


Once again thanks fr the tips Waross.




By the way itsmoked, I checked Graingers, they do carry the type of motor I mentioned above. I'll keep this in mind for ordering in the near future. Thanks!




 

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