PROBLEM PROBABLE CAUSE
SOLUTION
TROUBLE SHOOTING GUIDES
ELECTRIC MOTORS
Dies Down of main power supply
Stator shorts when motor Replace stator
warms up.
Motor Does Not Come Up Motor under designed for Replace with a larger motor
to Speed application
Voltage too low at motor Check across AC line and correct if possible
terminals
Line wiring to motor too small Install larger line wiring
Broken rotor bars Look for broken bars or end rings, replace motor.
60 cycle motor connected to Replace unit with a 50 cycle motor.
50 cycle line supply
Motor Takes Too Long Excessive load Replace with larger motor
to Accelerate
Loose connection(s) Check connections and tighten where necessary
Wrong Rotation Improperly wired to AC line Check wiring diagram on motor nameplate and correct.
(3 Phase) (Wrong sequence of phases) Reverse any two motor leads at line connection
Motor Overheats Motor overloaded Replace with larger motor.
(Temperature Rise Above
Ambient Greater Than Motor fan may be clogged with Remove fan cover and clean, replace fan cover
Nameplate Specifications) dirt preventing proper
ventilation
Motor (3 phase) may have Check to insure that all connections are tight
one phase open
Partially shorted stator coil Must be rewound
Line voltage too high Check across AC line and correct. Step-down
transformer may be required
Motor Overheats Line voltage too low Check across AC line. Consult power company.
-Continue- Step-up transformer may be required
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