Just a quick question regarding my available options for limiting motor inrush. I've got a 40's or 50's vintage Century capacitor start motor on my lathe - 1 horsepower, 1.25 service factor with a nameplate FLA of 12 as connected for 120V. Dual voltage, reversible. It is being supplied by a 15A general purpose branch circuit and controlled by a drum switch. Overload protection by Edison-base fuse.
There is approximately a 1 in 30 or 1 in 40 chance of said motor tripping the magnetic element in the circuit breaker protecting the branch circuit each time I start the motor. Being that it is in a lathe, it sees dozens of starts in an hour, not to mention occasional bursts of jogging.
My question is what sort of options are available on the market for limiting motor inrush on the line side of the controller? Due to the nature of this installation, trying to fit e.g. a starting torque limiter on the load side of the drum switch would be a pain right in the butt. I could easily end up being over on pipe and/or box fill if I were to try that.
Would a suitably sized choke in series with the incoming lines to the drum switch be the most elegant solution for clamping just a handful of amps without negatively impacting motor performance? Or are current-sensing torque limiters available which are designed to operate on the line side of the controller?
Thanks.
EDIT:
I just saw mention of Square D's High Magnetic line of QO circuit breakers. These seem to be exactly the right solution for this situation.
There is approximately a 1 in 30 or 1 in 40 chance of said motor tripping the magnetic element in the circuit breaker protecting the branch circuit each time I start the motor. Being that it is in a lathe, it sees dozens of starts in an hour, not to mention occasional bursts of jogging.
My question is what sort of options are available on the market for limiting motor inrush on the line side of the controller? Due to the nature of this installation, trying to fit e.g. a starting torque limiter on the load side of the drum switch would be a pain right in the butt. I could easily end up being over on pipe and/or box fill if I were to try that.
Would a suitably sized choke in series with the incoming lines to the drum switch be the most elegant solution for clamping just a handful of amps without negatively impacting motor performance? Or are current-sensing torque limiters available which are designed to operate on the line side of the controller?
Thanks.
EDIT:
I just saw mention of Square D's High Magnetic line of QO circuit breakers. These seem to be exactly the right solution for this situation.
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