34
For wire runs up to 50 ft (15 m), use no. 18 AWG (American Wire
Gage) insulated wire (35°C [95°F] minimum). For 50 to 75 ft (15
to 23 m), use no. 16 AWG insulated wire (35°C [95°F] minimum).
For over 75 ft (23 m), use no. 14 AWG insulated wire (35°C
[95°F] minimum). All wire sizes larger than no. 18 AWG cannot
be directly connected to the thermostat and will require a junction
box and splice at the thermostat.
UNIT WITHOUT THRU-BASE CONNECTION KIT
Correctly rated low voltage wire can be routed through the rubber
grommet located on the corner post adjacent to the control box ac
-
cess panel. Route wire through the grommet and then route the
wire behind the corner post utilizing the factory provided wire ties
secured to the control box. This will ensure separation of the field
low voltage wire and the high voltage circuit. Route the low volt
-
age wire to the Integrated Staging Control (ISC) board. See
Fig. 41.
Fig. 41 — Typical Low-Voltage Control Connections
NOTE: If utilizing the through the base connections, route the low
voltage wire through the wire ties to the Integrated Staging Con
-
trol (ISC) board (see Fig. 42).
Fig. 42 — Field Control Wiring Raceway
HEAT ANTICIPATOR SETTINGS
Set heat anticipator settings at 0.14 amp for the first stage and
0.14 amp for second-stage heating.
TRANSFORMER CONNECTION FOR 208-V POWER
SUPPLY
All units except 208/230-v units are factory wired for the voltage
shown on the nameplate. If the 208/230-v unit is to be connected
to a 208-v power supply, the control transformer must be rewired
by moving the black wire with the
1
/
4
-in. female spade connector
from the 230-v connection and moving it to the 208-v
1
/
4
-in. male
terminal on the primary side of the transformer. Refer to unit label
diagram for additional information.
RTU Open Control System
For details on operating units equipped with the factory-installed
RTU Open controller, refer to the
“Factory-Installed RTU Open
Multi-Protocol Controller Control, Start-Up, Operation and Trou
-
bleshooting”
manual.
SystemVu™ (Factory Option)
For details on operating 48LC 14-26 units equipped with the fac
-
tory installed SystemVu control option, refer to the
48/50LC 07-26
Single Package Rooftop Units with SystemVu Controls Version 1.X
Controls, Start-Up, Operation and Troubleshooting
manual.
C
G
C
G
O/B/Y2
Y2
R
R
Y1
Y1
Y3
Y3
(Note 1)
(Notes 2 & 3)
(Note 3)
W1
W1
W2
W2
T
H
E
R
M
O
S
T
A
T
Note 1: Typical multi-function marking. Follow manufacturer’s configuration
Instructions to select Y2.
Note 2: Y2 to Y3 connection required for 2 stage cooling operation and
when integrated economizer function is desired.
Note 3: To Connect a 2-Stage Thermostat:
Y2 to Y3 connection required for 2 stage cooling operation which
provides low and high cooling states.
Field Wiring
Integrated
Staging Control
(ISC) Board
Typical
Thermostat
Connections
RUBBER
GROMMET
CORNER
POST
WIRE
TIES
THRU THE BASE
CONNECTION
