AAON RQ NextGen Series, Installation Operation & Maintenance

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36
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.
It must be verified that proper motor rotation
and blower 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.
Table 3 – 35 KAIC Fuse Sizing
Table 4 – 65 KAIC Fuse Sizing
Variable Speed Compressors
Variable speed compressors with an inverter
drive are available on 2-6 ton units. Variable
speed compressors must not be operated
outside the factory determined frequency
range. The factory determined compressor
frequency range is given below in Table 5.
For more information on the variable speed
compressor, reference the RQ Series
35 KAIC Construction
Component Description
Interrupting
Rating (kA)
Fuse
Class CC,
600V, 0.5A - 30A
200
Fuse
Class J,
600V, 35A - 600A
200
Disconnect 3P, 600V, 15A -
600A
35
65 KAIC Construction
Component Description
Interrupting
Rating (kA)
Fuse
Class CC,
600V, 0.5A - 30A
200
Fuse
Class J,
600V, 35A - 600A
200
Disconnect 3P, 600V,
15A - 600A
65
Rotation must be checked on all
MOTORS AND COMPRESSORS of
three phase units. Supply fan, exhaust
fan, and condenser fan motors must
all be checked by a qualified service
technician at startup and any wiring
alteration must only be made at the
unit power connection.
CAUTION
Scroll compressors are directional
and will be damaged by operation in
the wrong direction. Low pressure
switches on compressors have been
disconnected after factory testing.
Rotation must be checked by a
qualified service technician at startup
using suction and discharge pressure
gauges and any wiring alteration must
only be made at the unit power
connection.
CAUTION