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LGM/LCM156, 180, 210, 240, 300
Electrical Connections - Power Supply
A-Wiring
Route field wiring in conduit between bottom power entry
and disconnect. See figure 8. This does not supersede
local codes or authorities having jurisdiction.
Do not apply power or close disconnect switch until
installation is complete. Refer to start-up directions.
Refer closely to unit wiring diagram.
Refer to unit nameplate for minimum circuit ampacity
and maximum fuse size.
1- Units are factory-wired for 240/460 volt supply. For
208V supply, remove the insulated terminal cover
from the 208V terminal on the control transformer.
Move the wire from the transformer 240V terminal
to the 208V terminal. Place the insulated terminal
cover on the unused 240V terminal.
2- Route power through the bottom power entry area
and connect to line side of unit disconnect, circuit
breaker or terminal block. See unit wiring diagram.
3-
Units With Optional 120v GFCI Outlet -
Route and connect separate 120v wiring to GFCI
outlets which do not have factory-installed wiring.
Route field wiring in conduit between bottom power
entry and GFCI. See figure 8.
SEAL
WATERTIGHT
RUN FIELD
WIRING IN
FIELD PRO
VIDED CONDUIT
SIDE ENTRY
KNOCKOUTS
BOTTOM
POWER ENTRY
OPTIONAL
120V GFI
MAKE-
UP BOX
FIGURE 8
FIELD WIRE ROUTING
B-Unbalanced Three-Phase Voltage
Units equipped with an inverter (VFD) are designed to
operate on balanced, three-phase power. Operating units
on unbalanced three-phase power will reduce the
reliability of all electrical components in the unit.
Unbalanced power is a result of the power delivery
system supplied by the local utility company.
Factory-installed inverters are sized to drive blower
motors with an equivalent current rating using balanced
three-phase power. When unbalanced three-phase
power is supplied; the installer must replace the existing
factory-installed inverter with an inverter that has a higher
current rating to allow for the imbalance. Use table 2 to
determine the appropriate replacement inverter.
TABLE 2
INVERTER UP-SIZING
Factory-Installed Inverter HP
Replacement Inverter HP
2
5
3
7-1/2
5
10
7.5
15
10
20
Electrical Connections - Control Wiring
A-Thermostat Location
Room thermostat mounts vertically on a standard 2” X 4”
handy box or on any non-conductive flat surface.
Locate thermostat approximately 5 feet (1524mm)
above the floor in an area with good air circulation at
average temperature. Avoid locating the room
thermostat where it might be affected by:
-drafts or dead spots behind doors and in corners
-hot or cold air from ducts
-radiant heat from sun or appliances
-concealed pipes and chimneys
B-Wire Routing
Route thermostat cable or wires from subbase through
knockout provided in unit. Use 18 AWG wire for all
applications using remotely installed electro-mechanical
and electronic thermostats.
On hot gas reheat units, route wires from RH sensor or
remote switch through knockout provided in unit. For
sensor installations, use 22AWG stranded, two twisted
pairs, individually shielded, 100% aluminum shield with
drain wire and Teflon jacket.
IMPORTANT - Unless field thermostat wires are rated for
maximum unit voltage, they must be routed away from
line voltage wiring.
