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Power wiring is to the unit terminal block or main
disconnect. All wiring beyond this point has been
done by the manufacturer and cannot be modified
without affecting the unit's agency/safety
certification.
All units require field supplied electrical
overcurrent and short circuit protection. Device
must not be sized larger than the Maximum
Overcurrent Protection (MOP) shown on the unit
nameplate.
Supply voltage must be within the min/max range
shown on the unit nameplate. Available short
circuit current must not exceed the short circuit
current rating (SCCR) shown on the unit
nameplate.
Three phase voltage imbalance will cause motor
overheating and premature failure. The maximum
allowable imbalance is 2%.
Voltage imbalance is defined as 100 times the
maximum deviation from the average voltage
divided by the average voltage.
Example:
(221V+230V+227V)/3 = 226V, then 100*(226V-
221V)/226V = 2.2%, which exceeds the allowable
imbalance.
Check voltage imbalance at the unit disconnect
switch and at the compressor terminal. Contact
your local power company for line voltage
corrections.
NOTE: Startup technician must check for proper
motor rotation and check fan motor amperage
listed on the motor nameplate is not exceeded.
Motor overload protection may be a function of
the variable frequency drive and must not be
bypassed.
Wire control signals to the unit’s low voltage
terminal block located in the controls
compartment.
Rotation must be checked on all
MOTORS AND COMPRESSORS of
three phase units. Condenser fan
motors must be checked by a qualified
service technician at startup and any
wiring alteration must only be made at
the unit power connection. Variable
frequency drives are programmed to
automatically rotate the fan in the
correct rotation. Do not rely on fans
with variable frequency drives for
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