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Electric Motors/High current reading

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Question
I have a 3hp induction motor on my table saw. It has a running current on the nameplate of 18 amps. I have been tripping a 30 amp breaker so i checked the running current on both phases and measred 27amps on both phases. The nameplate data is as follows
3hp
60 hz
230vac
18amps
3450rpm
1phase
2 pole
60 deg C
Class A
1985

I confirmed the voltage to be 250vac ph/ph 125vac ph/gnd. The motor sounds good and spins freely. The only issue is with the centrifugal switch. I believe it is releasing but not sure and the spring metal contact plate stop is broken off and is likely dragging on the centrifugal switch.

Answer
It seems the centrifugal switch is not releasing. But if this was the case the capacitors would be shorted out.
remove the belts and start the motor by by it self.
Motor should start right away, and the running current should be approx. 7-9 amps.
If it isnt, then the centrifugal switch is no good or the stationary switch contacts are shot.

Electric Motors

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Harcharan Singh Diocee

Expertise

Electric motor winding redesign, AC and DC. Troubleshooting, motors controls generators. Vibration analysis, dynamic balancing, root cause analysis: electrical and mechanical.

Experience

thirty five years electro-mechanical and Senior Management

Organizations
EASA, CSA, ASTTBC, FSR

Education/Credentials
Journeyman Motor Rewinder, Millwright, Industrial Electrician, Vibration Analyst level II. Certified Electrical Technician ASTTBC, FSR Class B, in BC. Laser alignment specialist. Marine machinery repairs. Business Management Certificate. Last 19 yrs as Plant Manager

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