Max possible start torque with an overvoltage or?
Max possible start torque with an overvoltage or?
(OP)
I have an application where a gearmotor needs to run for one second three times a day. During this brief period it needs to produce a minimum of 18 in-lb. I want the motor to be as small as possible for low rotor inertia, light weight, low cost and it needs to be TENV. I would like to do this with an 1/8hp motor since they come std. TENV.
What can I do to get 18 in-lb out of an 1/8hp motor for a very short period of time. The voltage on site 1 phase 115VAC. The actual duty cycle will be approx. .25 sec FWD, brake for .25 sec., .25 sec REV, brake for .25 sec. They should be at least 1 hour between each cycle. I am hoping the brake will be mechanical.
Some of the things I am thinking about would be running the motor with a higher than rated voltage (step up xfmr),oversized capacitors, alternative motor wiring or even alternative windings.
Thanks in advance, Barry1961
What can I do to get 18 in-lb out of an 1/8hp motor for a very short period of time. The voltage on site 1 phase 115VAC. The actual duty cycle will be approx. .25 sec FWD, brake for .25 sec., .25 sec REV, brake for .25 sec. They should be at least 1 hour between each cycle. I am hoping the brake will be mechanical.
Some of the things I am thinking about would be running the motor with a higher than rated voltage (step up xfmr),oversized capacitors, alternative motor wiring or even alternative windings.
Thanks in advance, Barry1961





RE: Max possible start torque with an overvoltage or?
1 second is pretty darned short. Depending on what you are trying to accomplish maybe a NEMA design D torque speed characteristic would help?
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RE: Max possible start torque with an overvoltage or?
You need 18 Lb-in = 1.5 Lb-ft =24 oz-feet
The torque increases with a ratio of voltage proportion squared until magnetic saturation is reached.
Hopefully you are right on the money with 1/8 HP 4 Poles, so no need for overvoltage.
You could buy TEFC motor and remove the fan.
RE: Max possible start torque with an overvoltage or?
Quando Omni Flunkus Moritati
RE: Max possible start torque with an overvoltage or?
http://www.thomasregister.com
and type Motors: Electric under Product or Service, which will return 508 companies to approach to. It may be a good idea to coordinate your effort with the motor sales representative to obtain the motor parameters, cost, etc. since they have all information that you need at their fingertips.
RE: Max possible start torque with an overvoltage or?
Barry1961
RE: Max possible start torque with an overvoltage or?
Thanks for the feedback, let us know how your selection worked.