AAON H3 Series, Установка, эксплуатация и обслуживание

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Size supply conductors based on the unit
Minimum Current Ampacity (MCA) rating.
Supply conductors must be rated a minimum
of 75
°
C (167
°
F).
Protect the branch circuit in accordance with
code requirements. The unit must be
electrically grounded in accordance with
local codes, or in the absence of local codes,
the
current National Electric Code,
ANSI/NFPA 70 or the current Canadian
Electrical Code CSA C22.1.
Note: Units are factory wired for 208V,
230V, 460V or 575V. In some units, the
208V and 230V options may also be provided
in single or three phase configurations. The
transformer configuration must be checked
by a qualified technician prior to startup.
Wire power leads to the unit’s terminal block
or main disconnect. All wiring beyond this
point has been completed by AAON and
cannot be modified without effecting the
unit’s agency/safety certification.
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.
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 that is
between 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
Three phase voltage imbalance will
cause
motor overheating and
premature failure.
CAUTION
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