Product Manual

-67-
AC Motor Trouble-Shooting Chart (cont’d)
Problem Likely Causes What To Do Motor overload protector Ambient temperature too high. Verify that the motor is getting enough air for proper cooling. continually trips. (cont’d) Most motors are designed to run in an ambient temperature of less than 40° C. (Note: A properly operating motor may be hot to the touch.) Protector may be defective. Replace the motor’s protector with a new one of the same rating. Winding shorted or grounded. Inspect stator for defects, or loose or cut wires that may cause it to go to ground. Motor vibrates. Motor misaligned to load. Realign load. Load out of balance. Remove motor from load and inspect motor by itself. Verify that (Direct drive application). motor shaft is not bent. Rule of thumb is .001” runout per every inch of shaft length. Motor bearings defective. Test motor by itself. If bearings are bad,you will hear noise or feel roughness. Replace bearings. Add oil if the bearing is a sleeve bearing type or replace bearings. Add grease if bearings have grease fittings. Rotor out of balance. Inspect motor by itself with no load attached. If it feels rough and vibrates but the bearings are good, it may be that the rotor was improperly balanced at the factory. Rotor must be replaced or rebalanced. Motor may have too much endplay. With the motor disconnected from power turned shaft. It should move but with some resistance. If the shaft moves in and out too freely, this may indicate a preload problem and te bearings may need additional shimming. Winding may be defective. Test winding for shorted or open circuits. The amps may also be high. Replace motor or have stator rewound.