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9
UNIT COMPONENT DAMAGE HAZARD
Failure to follow this caution may result in damage to the unit
being installed.
1. Make all electrical connections in accordance with NEC
ANSI/NFPA (latest edition) and local electrical codes
governing such wiring. In Canada, all electrical
connections must be in accordance with CSA standard
C22.1 Canadian Electrical Code Part 1 and applicable local
codes. Refer to unit wiring diagram.
2. Use only copper conductor for connections between
field--supplied electrical disconnect switch and unit. DO
NOT USE ALUMINUM WIRE.
3. Be sure that high--voltage power to unit is within operating
voltage range indicated on unit rating plate. On 3--phase
units, ensure phases are balanced within 2 percent. Consult
local power company for correction of improper voltage
and/or phase imbalance.
4. Do not damage internal components when drilling through
any panel to mount electrical hardware, conduit, etc.
!
CAUTION
HIGH--VOLTAGE CONNECTIONS
The unit must have a separate electrical service with a
field--supplied, waterproof disconnect switch mounted at, or within
sight from the unit. Refer to the unit rating plate, NEC and local
codes for maximum fuse/circuit breaker size and minimum circuit
amps (ampacity) for wire sizing (See Table 3 for electrical data).
The field--supplied disconnect may be mounted on the unit over the
high--voltage inlet hole when the standard power and low--voltage
entry points are used. See Fig. 2 and 3 for acceptable location.
See unit wiring label and Fig. 11 for reference when making high
voltage connections. Proceed as follows to complete the
high--voltage connections to the unit.
Single phase units:
1. Run the high--voltage (L1, L2) and ground lead into the
control box.
2. Connect ground lead to chassis ground connection.
3. Locate the black and yellow wires connected to the line side
of the contactor.
4. Connect field L1 to black wire on connection 11 of the
compressor contactor.
5. Connect field wire L2 to yellow wire on connection 23 of the
compressor contactor.
Three--phase units:
1. Run the high--voltage (L1, L2, L3) and ground lead into the
control box.
2. Connect ground lead to chassis ground connection.
3. Locate the black and yellow wires connected to the line side
of the contactor.
4. Connect field L1 to black wire on connection 11 of the
compressor contactor.
5. Connect field wire L2 to yellow wire on connection 13 of the
compressor contactor.
6. Connect field wire L3 to blue wire from compressor.
SPECIAL PROCEDURES FOR 208--V OPERATION
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Make sure that the power supply to the unit is switched OFF
and lockout tag installed before making any wiring changes.
!
WARNING
CONTROL VOLTAGE CONNECTIONS
NOTE
:Do not use any type of power--stealing thermostat. Unit
control problems may result.
Use no. 18 American Wire Gage (AWG) color--coded, insulated
(35
°
C minimum) wires to make the control voltage connections
between the thermostat and the unit. If the thermostat is located more
than 100 ft from the unit (as measured along the control voltage
wires), use no. 16 AWG color--coded, insulated (35
°
C minimum)
wires.
STANDARD CONNECTION
Remove knockout hole located in the electric heat panel adjacent to
the control access panel. See Fig. 2 & 3. Remove the rubber
grommet from the installer’s packet (included with unit) and install
grommet in the knockout opening. Provide a drip loop before
running wire through panel.
Run the low--voltage leads from the thermostat, through the inlet
hole, and into unit low--voltage splice box.
Locate five 18--gage wires leaving control box. These low--voltage
connection leads can be identified by the colors red, green, yellow,
brown (See Fig. 11). Ensure the leads are long enough to be routed
into the low--voltage splice box (located below right side of control
box). Stripped yellow wire is located in connection box. Route leads
through hole in bottom of control box and make low--voltage
connections (See Fig. 11). Secure all cut wires, so that they do not
interfere with operation of unit.
TRANSFORMER PROTECTION
The transformer is of the energy--limiting type. It is set to withstand
a 30--second overload or shorted secondary condition.
POWER
SUPPLY
FIELD-SUPPLIED
FUSED DISCONNECT
HIGH VOLTAGE
POWER LEADS
(SEE UNIT WIRING
LABEL)
GND
CONTROL BOX
SPLICE BOX
LOW-VOLTAGE
POWER LEADS
(SEE UNIT
WIRING LABEL)
Y
G
R
C
YEL(Y)
GRN(G)
RED(R)
BRN(C)
THERMOSTAT
(TYPICAL)
LEGEND
Field Control-Voltage Wiring
Field High-Voltage Wiring
NOTE: Use blue wire for 3-phase units only.
C99010
Fig. 11 -- High-- and Control--Voltage Connections
50SD