1. How to dry the dampened motors?

It is best to send the dampened motors to specialized repairing center for drying. If it is impossible, you can treat with the motor by yourselves. The motor can be connected with 220V single phase power supply, i.e., three entry cables connected with single-phase live wires, other exiting cables connected with neutral wires. If the motor is slightly dampened, it will take two hours, if it is seriously dampened, it will take one or two days. After drying, to use megohmmeter to test insulation resistance, the value should be not less than 0.5M Ω.   

2. How to do with unbalanced three phase currents?

When three phase power supply is balance, no load current of any phase is less than 10% comparing with average current of three phases.

The most problems of unbalanced three phase raised by consumers are caused by the problems of power supply, including unbalanced voltage and poor connection with terminals, the checking method is to exchange the phase of power supply, must exchange it at the terminals inside the T-box, thus it can clearly judge the faults outside of motor. Assuming the terminals sequence is U、V、W， now exchange that into W、U、V，thus it can keep the same rotating direction. After exchanging the sequence, if higher or lower phase current changes accordingly, that is to say power supply has problems. If it doesn’t change, that is to say motor has problems possibly. But sometimes consumer take star delta starting, six lines come out, adopt the same method on upper three lines, if not, exchange the lower three lines.

3. How to do with the overload?

Remove the conveying belts and turn the axis of driven machine, to see whether the rotating is flexible. If it is not flexible, must find out the reason and repair it.  If it is flexible, to regulate the equipment, reduce the flow of water pump, air flow of fan, and feed of supply machines, thus can decrease the load.

4. How to do with lack of phase?

When lack of phase occur on motor, normally happens at the leading wires except the windings, after checking whether phase fuse is broken, terminals are loose and leading wires is shut, then to eliminate that fault.

5. The causes for overheated bearings, and how to with it separately?

The causes for overheated bearings as following:

（1）bearing damaged，to replace new bearings；

（2）more or less lubricating grease or bad quality ，to lubricate with fresh grease；

（3）loose or tight on fit between bearing and shaft, to mend the surface part of fixing bearing；

（4）loose or tight on fit between bearings and end-shield, to replace the end-shield；

（5）tight belts, to regulate belts；

（6）bad installing on coupling cause eccentricity of motor and equipment, to regulate  concentricity.