Is it Advisable to Run a 3 Phase Motor Off of 1 Phase using a Capacitor ?
Patrick, Thu Jun 02 2022, 10:22PMI work with a supposed Electrical Engineer who is from a third world country and he continues to tell me while we were fixing a motor conveyor that its possible to run a 3 phase motor off single phase using a single capacitor. Its sort of scary working with him on 240/480 when he talks like this.
Is this advisable ? Ive scene some sketchy youtube videos showing how to do it but it seems like this should cause phase distortion, power factor heating, motor heating, circuit breaker heating and speed/torque issues. All of which would lead to a short life and unstable rotation. And is the capacitor vulnerable to catching on fire or failing in some way ?
Thank you for feedback.
Re: Is it Advisable to Run a 3 Phase Motor Off of 1 Phase using a Capacitor ?
Carbon_Rod, Fri Jun 03 2022, 12:42AM
Depends on the motor, but it sounds a little dangerously muddled for general advice. He probably means the lag capacitor on smaller AC motors, which among other things usually ensure it spins in the right direction.
Jam a current-controlled VFD and output-conditioner on a switching-rated motor if you are ever unsure of the power quality or $/hp. Also, a magnetic safety interlock switch is usually a code requirement in most places where amputations are not a business opportunity.
Carbon_Rod, Fri Jun 03 2022, 12:42AM
Depends on the motor, but it sounds a little dangerously muddled for general advice. He probably means the lag capacitor on smaller AC motors, which among other things usually ensure it spins in the right direction.
Jam a current-controlled VFD and output-conditioner on a switching-rated motor if you are ever unsure of the power quality or $/hp. Also, a magnetic safety interlock switch is usually a code requirement in most places where amputations are not a business opportunity.
Re: Is it Advisable to Run a 3 Phase Motor Off of 1 Phase using a Capacitor ?
klugesmith, Fri Jun 03 2022, 02:09AM
If the motor runs, wired his way, some simple measurements might give you confidence or not.
How could you be abusing the motor if its three phase currents, and its three phase-to-phase voltages, are roughly matched?
I agree with need for proper start/stop button switch, for safety in case of power outage etc.
klugesmith, Fri Jun 03 2022, 02:09AM
If the motor runs, wired his way, some simple measurements might give you confidence or not.
How could you be abusing the motor if its three phase currents, and its three phase-to-phase voltages, are roughly matched?
I agree with need for proper start/stop button switch, for safety in case of power outage etc.
Re: Is it Advisable to Run a 3 Phase Motor Off of 1 Phase using a Capacitor ?
Patrick, Fri Jun 03 2022, 04:19AM
This is the schematic. It doesn't seem to be balanced in any way I can see.
Patrick, Fri Jun 03 2022, 04:19AM
This is the schematic. It doesn't seem to be balanced in any way I can see.
Re: Is it Advisable to Run a 3 Phase Motor Off of 1 Phase using a Capacitor ?
Patrick, Fri Jun 03 2022, 04:20AM
cant seem to post it.
Patrick, Fri Jun 03 2022, 04:20AM
cant seem to post it.
Re: Is it Advisable to Run a 3 Phase Motor Off of 1 Phase using a Capacitor ?
klugesmith, Mon Jun 06 2022, 05:17PM
>> cant seem to post it.
That's why this once-vibrant forum dried up. The hard-to-read captchas are a comparatively minor nuisance.
klugesmith, Mon Jun 06 2022, 05:17PM
>> cant seem to post it.
That's why this once-vibrant forum dried up. The hard-to-read captchas are a comparatively minor nuisance.
Re: Is it Advisable to Run a 3 Phase Motor Off of 1 Phase using a Capacitor ?
Patric, Mon Jun 06 2022, 06:48PM
Yes.
Patric, Mon Jun 06 2022, 06:48PM
Yes.
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