ELECTRICAL CONNECTIONS
Wire Transformer Kit or Electric Heater per wiring diagram on the
accessory. Typical field wiring is shown in Figures 9, 10 and 11.
CAUTION: Break off tab must be removed from 2HW electric
heat control boards for variable speed operation. See
Figure 6.
NOTE: All wiring must comply with local and national electrical
code requirements. Read and heed all unit caution labels.
LINE POWER CONNECTIONS
Power may be brought into the unit through the supply air end of
the unit (top when unit is vertical) or the right side panel. Use the
hole appropriate to the unit’s orientation in each installation to
bring conduit from the disconnect. The power lead conduit should
be terminated at the transformer or electric heater box. Refer to
Tables 2 and 5 for single source wire sizes. Also see Figure 5.
ALTERNATE LINE POWER CONNECTIONS
When desired or required by local conditions the units equipped
with circuit breakers may be field converted to use multiple power
sources, this will permit the use of smaller size power wire but will
require a greater number of wires. To accomplish this field con-
version refer to Figure 5 - (Dual Supply) as an example and
proceed as follows.
1. Remove the jumper bar assembly and cover at the line side
connection to the circuit breakers.
2. Select the proper wire size from Table 3.
3. Connect the multiple power sources direct to the circuit breakers.
NOTE: LINE VOLTAGE POWER CONNECTS
DIRECTLY TO 10 KW BOARDS
EDGE CONNECTOR
(For Wiring Harness that
attaches to Connection Board)
BREAK OFF TABS
(For Variable Speed Air
Handler ONLY - must be
removed)
5, 7.5 & 10 KW CONTROL BOARDS
EDGE CONNECTOR
(For Wiring Harness that
attaches to Connection Board)
12.5, 15 & 20 KW CONTROL BOARDS
BREAK OFF TABS
(For Variable Speed Air
Handler ONLY - must be
removed)
GRD.
LUG
DUAL SUPPLY
SINGLE SUPPLY
POWER WIRING
NOTE: Two circuits permit smaller wire.
POWER
SUPPLY
WITHOUT CIRCUIT BREAKER
WITH CIRCUIT BREAKER
GRD.
GRD.
LUG
GRD.
CIRCUIT BREAKERS
POWER
SUPPLY
GRD.
LUG
GRD.
CIRCUIT BREAKERS
POWER
SUPPLY 1
POWER
SUPPLY 2
WITH CIRCUIT BREAKER
FIELD
REMOVED
BUSSBAR
FIGURE 5 - Line Power Connections
FIGURE 6 - Typical Electric Heat Control Boards - (5-20KW Single Phase)
535.03-N1Y
Unitary Products Group
5
