54
YORK INTERNATIONAL
HANDLING REFRIGERANT FOR
DISMANTLING AND REPAIRS
MEGGING THE MOTOR
If it becomes necessary to open any part of the refriger-
ant system for repairs, it will be necessary to remove the
charge before opening any part of the unit. If the chiller is
equipped with optional valves, the refrigerant can be iso-
lated in either the condenser or evaporator / compressor
while making any necessary repairs.
While the main disconnect switch and compressor
motor starter are open, meg the motor as follows:
1. Using a megohm meter (megger), meg between
phases and each phase to ground (see Fig. 23);
these readings are to be interpreted using the graph
shown in Fig. 24.
2. If readings fall below shaded area, remove exter-
nal leads from motor and repeat test.
NOTE: Motor is to be megged with the starter at
ambient temperature after 24 hours of idle
standby.
FIG. 23
DIAGRAM, MEGGING MOTOR WINDINGS
LD00475