Motor Diagnostic System

Hi, what kind of info are you expecting. I can point you to a system which measures torque output, currency-, voltage input. Vibration, etc. Let me know if I you want more info's. Cheers

Hi.... Eng. KUNOMARS,

I'm looking for a system that monitor the vibration, I'll appreciate if you can help me in same topic.

Hi Megatron.

Diagnostic operations are allow for adjustments. However no adjusment is possible for electric motors. Therefore what you need is a common inspection system. If yes, pls find below some common ways. Below mentioned items are not covering Brush type AC or DC motors. İnspection procedure for brush motors are different.

The first check would be physical. Turn the rotor by hand to check for any friction, How is the Condition of the ball bearings, Bearing houses in the front or rear covers, How tight between the shaft and bearings? Is cooling fan O.K Any cracks on the body and shoes? Terminal box and terminal inside.etc.

Now coming to electrical checks. If the motor have burnt and rewound before, always approach with suspection. Ex-factory windings are always different and it is difficult to match this later by hand winding.

Electrical checks are achieved in three steps. Before all electric tests, open the terminal box and smell inside for any odour indication of burning.

First check is for any broken winding, by using an ordinary ohmmeter.

Second check is for short connection between separate windings, as well as the Motor body itself. Again with Ohmmeter. Do not forget to remove all the bridges in the terminal box

Third test is the check for insulation. Use Megger for this test. Check for any connectivity, sourced by humidity, between each separate windings and also wth motor body. The resistance you would read must be over 1 Megaohm at all measurements. Otherwise the motor needs a varnish or epoxy bath and later a few hours in the oven

Now the last check. You must have a special device to achieve this last test.

The goal of this test is to check if any winding of any phase coil is shorted inside. You cannot find it with any of sophisticated ohmmeter. You need AC current to pass from the coils, and a clamp type ammeter to measure this.

Find a 1 KVA insulation transformer, of which primary side is suitable for your mains supply. Secondary side is for 42 Volt AC output. Connect this 42 Volt AC seperately for each coils Such as First U-X, then later V-Y, and later W-Z. The motor will sound Hummm and the rotor may try to move. Read the current by using clamp meter. Note each readings.

Since each of the phase windings should be identical, the readings must be the same or very close to each other. If one coil shows much Amp. then the others you can be sure abt. one or few loops of that coil have burnt and created a closed loop. The motor is needed to rewound.

That' all. You can apply those tests for any ordinary three phase motors. Single phase motors are needed for an extra check for the capacitor.

Inspecting the capacitor values needs calculation, I can mention later if needed.

Kindest Regards

Hi..... Eng. nezihozfirat,

your information more than usefull, I'll be benefit of them in my report.

Thank you very much

google bently nevada...or metrix... they will be able to help you