AAON V3 Series - Figure 16 - H3 Internal Control Panel Electrical Connections

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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.
A qualified technician must check for proper
motor rotation and check blower motor
amperage listed on the motor nameplate is
not exceeded.
Wire control signals to the unit’s low voltage
terminal block located in the controls
compartment.
If any factory installed wiring must be
replaced, use a minimum 105°C (221°F) type
AWM insulated conductors.
Thermostat Control Wiring
If a thermostat is used for unit control, locate
the thermostat on an inside wall 1.2 and 1.5
meters (4-5 feet) above the floor where it will
not be subjected to drafts, sun exposure, or
heat from electrical fixtures of appliances.
Control wiring must deliver adequate voltage
to components to assure proper operation.
Control voltage returning from controller
circuit must be a minimum of 21 VAC. To
assure proper wiring use the following chart
to determine the allowable wiring distances.
Table 5 - Control Wiring
Wire Size
(Stranded)
Copper
Conductors Only
Total Wire Distance
Allowable
20 AWG
61 m
200 ft
18 AWG
106.7 m
350 ft
16 AWG
152.4 m
500 ft
14 AWG
228.6 m
750 ft
12 AWG
381.0 m
1250 ft
Total Wire Distance Allowable =
(Quantity of Control Wires) x
(Control Wire Distance)
Take the total wire distance allowable and
divide by the number of wires to be
connected. This indicates the distance
allowable for that size wire. The wiring to the
unit must not exceed the total wire distance
allowable. If the voltage at the connectors is
less than 21 VAC, isolation relays must be
installed. If under external control 21 VAC
must be field verified.
All external devices must be powered via a
separate external power supply.
Example:
A total of 8 wires must be pulled 75ft
(22.9 m) to a control the unit. What size wire
must be used?
According to the Table 5, 16 AWG allows for
63ft (500 ft/8 wires) and 14 AWG allows for
94ft (750 ft/8 wires). Thus, 14 AWG must be
used.
Rotation must be checked on all
MOTORS of three phase units.
Supply 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