Minimum test value for a good electric motor is at least 1mω running amps test with the motor running check the full load amps fla with a suitable meter or preferably a clamp on meter and compare with the motor name plate fla.
Electric motor testing.
Electric motors have had a reputation for being a mix of science and magic.
Ideally the meter should barely move off the highest resistance indication.
When a motor isn t working right or fails you can use testing to track down the most probable cause of the problem.
Many electric motor failures are caused by bearing failures.
Testing electric motors doesn t have to be a mystery.
The bearings allow the shaft or rotor assembly to turn freely and smoothly in the frame.
Most electric motors whether ac or dc fail after time for reasons that may not be electrical in nature.
When an electric motor fails to start runs intermittently runs hot or continually trips its overcurrent device there my be a variety of causes.
And press a test probe to this spot and the other test probe to each of the motor leads one at a time.
Motors without brushes and commutators such as ac alternating current induction motors last the longest because of few moving parts.
The electric power research institute epri conducted a survey which brought into the light that 48 of motor failures are because of electrical.
And electrical failures require your maintenance group to go about testing the motors in your care.
Electric motor testing is usuallly the first thing to be sacrificed when cutting back on operational expenses.
But smart companies understands is that what this means for maintenance programs is billions of dollars of lost revenue through increased motor repair costs downtime and waste in industrial and commercial companies.
Sometimes the trouble lies within the power supply.
The electrician or maintenance person must have this skill to determine the electrical motor condition defected or cannot use anymore it can save.
Basic motor testing with multimeters and ammeters.
Deviations from rated fla could signify problems with the motor under test.
Static electric motor testing looks at the motor s insulation system while online or dynamic electric motor monitoring can identify issues regarding power quality and.
So when a motor fails to operate it may not be obvious what the problem is.
July 1 2015 by david herres 14 comments.
Knowledge of the basics together with powerful new test equipment vastly simplifies the job.
A motor is one part of a machine system and there are three areas of concern we must address.
Check c to e s to e r to e.
Ac and dc brush type motors such as those used in vacuum cleaners and power tools produce high power.
The power quality supplying the motor the motor itself and the driven load.
After bearing failure electrical faults are the most common mode of motor failure so in addition a properly planned electrical testing scheme is important for making sure of the plant reliability.
