AAON SB-018 - Manual (Page 24)

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foam at the cut. The edges and corners that
are not covered should then be sealed using
silicone caulking or a duct seal compound.
If a reciprocating saw is used to make the
cut-out take care that the metal skins of the
foam part do not separate from the foam,
this would result in reduced structural
integrity of the part.
Size supply conductors based on the unit
Minimum Current Ampacity (MCA) rating.
Supply conductors must be rated a minimum
of 75°C.
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 should 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 2.0%.
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.
Installing contractor must check for proper
motor rotation and check blower motor
amperage listed on the motor nameplate is
not exceeded.
Three phase voltage imbalance will
cause motor overheating and
premature failure.
CAUTION
Rotation must be checked on all
MOTORS AND COMPRESSORS of
three phase units. Supply fan motors
should all be checked by a qualified
service technician at startup and any
wiring alteration should only be made
at the unit power connection.
CAUTION