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Electric Motors/115/230v ac runs then trips breaker


Ok I have a surface grinder motor is ge 115/230 1/2hp fr56c model 5kc38lg134  rpm 3450 phase 1. It is wired for 110v I turn it on and the motor will start to ramp up speed then it sounds like it clicks and knocks down the speed. Then speeds back up than gets knocked back down . It never gets to full rpm it does that a couple times  then it will trip breaker... Please help is it the capacitor? Do I need a new motor? I know a little with electrical but this has me stumped.  
Thanks in advanced,

Itsounds like the the start winding is energizing when turned on, and when the centrifugal switch 'clicks' and shut off the start winding the it slows down because the run winding is not getting emergized. So maybe the run winding is shorted out or is open circuit.
Check the over temp Klixon, maybe it is tripped and is connected in the run circuit only.
You may have to dismantle the motorto do this.
OR if there is a run capacitor in circuit, it may be shorted or open.
hope this helps  

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Harcharan Singh Diocee


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


thirty five years electro-mechanical and Senior Management


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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