AAON SA-023, Installation Operation & Maintenance

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Note: Locations for field cut electrical
entries are marked on the unit. Field cut
openings must be a minimum of 6 inches
away from all components and wiring to
prevent damage due to drilling or cutting.
To pass wires through the wall or roof of the
unit, a hole should be cut and conduit passed
through it. Use the following procedure to
cut a round hole in a foam panel.
Cutting Electrical Openings
1. Locate the placement of the hole. Be sure
that the conduit will not interfere with the
operation of any component or prevent
access of any door or removable panel.
2. Drill a pilot hole all the way through the
foam panel.
3. Using a hole saw cut the hole through the
metal on both sides of the foam part.
4. With a knife cut the foam out of the hole.
5. After the conduit is installed in the hole
caulk the entire perimeter of the hole on
both sides with an industrial grade silicone
sealant or a duct seal compound.
If a larger cut-out is needed for additional
duct connections not provided by the
factory, or for any other reason, it is very
important that the foam be completely
sealed.
Insulation covers should be
fabricated from sheet metal to cover the
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: All units are factory wired for
208/230V, 460V, or 575V. If unit is to be
connected to a 208V supply, the transformer
must be rewired to 208V service. For 208V
service interchange the yellow and red
conductor on the low voltage control
transformer.
Red-Black for 208V
Yellow-Black for 230V
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.
Three phase voltage imbalance will
cause
motor overheating and
premature failure.
CAUTION