under amping motor
under amping motor
(OP)
I have a single phase 230 volt Dayton exaust fan motor. It's rated for 15 amps but only drawing 7. It is overheating and shutting down. Any suggestions to why?
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RE: under amping motor
RE: under amping motor
RE: under amping motor
RE: under amping motor
RE: under amping motor
RE: under amping motor
RE: under amping motor
RE: under amping motor
Any chance the motor is roof-mounted and exhausting air from cooking equipment? In smaller single-phase motors, internal thermal protectors are sometimes furnished. High- ambient temperature could be cycling the motor.
Also, the motor may be fed by a 3ø magnetic starter with an (undersized for the 1ø motor) automatic-reset overload relay.
RE: under amping motor
RE: under amping motor
RE: under amping motor
RE: under amping motor
How is this shutting down, is the fuse blowing, it just quits and must cool down to run again, what happens when it quits? Are there motor oveloads in the circuit? If so, were these changed out when re-wired for single phase... may have been OK for 3Ø but marginal for single...
RE: under amping motor
RE: under amping motor
RE: under amping motor
RE: under amping motor
bkboss - I hope you do not take this as an insult, not intended as that.
You need a more talented crew for maintenance. Tell headquarters to get someone out there that understands this stuff. I appreciate that you probably already realize this, which is why you are involved, which you probably resent, which ...
Here are the problems that I see:
How do you know that the original motor "burned" up? Did they take the motor apart and examine it? We require that no motor be replaced ever without the technician first committing to a diagnosis as to why the motor failed, and then fixing the problem that burned up the orignal motor if there is a problem elsewhere.
Why would they change a three phase motor to a single phase motor? Big mistake, bad choice, bad decision, sign of ignorance, UNLESS you somehow changed three phase power in the building to single phase.
Busbar is exactly correct about the starter (as he usually is). If the contactor and overload are IEC style, then the new single phase motor must be connected to the old three phase contactor, whith a transfer wire taking the current for one of the phases through the pole not being used any longer, otherwise the overload trip curve will be dramatically shortened and cause problems.
Seeing and speculating what you are dealing with on the technician end, how can you trust anything they do? Is the new motor the same rpm, same horsepower, same torque? Anything they have done is suspect.
On an immediate basis, require that they put the correct motor back in, (3 phase), as specified by the OEM of the equipment. Then talk calmly to the maintenance department if you can and see if they can find a supervisor that is a quaified electrician that also has knowledge about motors.
If the level of competence in the maintenance department is too low, your stores will become what I call "full of fleas". After a few years you will have nothing but jury rigged equipment, faulty connections, poor workmanship, improperly installed equipment, and you will be soooo very miserable, like a dog that cannot walk he has to scratch so much.
PUMPDESIGNER
RE: under amping motor