Installation Guide

WIRING INSTRUCTIONS
Wired for single
phase power
(24 volt control
models).
Factory wired
for single phase
power (line
voltage control
models).
Factory wired for
3-phase power
(24 volt control
models).
Wired for
3-phase power
(line voltage
control models)
FRONT
FRONT
BACK
BACK
FRONT
FRONT
BACK
BACK
Orange
wire
Orange
wire
Terminal
block
Heater
elements
Orange
wire
Orange
wire
Orange
wire
Red
wire
Red
wire
Red
wire
Red
wire
Junction block
for field wiring
Orange
wire
Terminal
block
Heater
elements
Junction block
for field wiring
Orange
wire
Terminal
block
Heater
elements
Junction block
for field wiring
Orange
wire
Terminal
block
Heater
elements
Junction block
for field wiring
Contactor
Contactor
Wired for single
phase power
(24 volt control
models).
Factory wired
for single phase
power (line
voltage control
models).
Factory wired for
3-phase power
(24 volt control
models).
Wired for
3-phase power
(line voltage
control models)
FRONT
FRONT
BACK
BACK
FRONT
FRONT
BACK
BACK
Orange
wire
Orange
wire
Terminal
block
Heater
elements
Orange
wire
Orange
wire
Orange
wire
Red
wire
Red
wire
Red
wire
Red
wire
Junction block
for field wiring
Orange
wire
Terminal
block
Heater
elements
Junction block
for field wiring
Orange
wire
Terminal
block
Heater
elements
Junction block
for field wiring
Orange
wire
Terminal
block
Heater
elements
Junction block
for field wiring
Contactor
Contactor
CAUTION: TO AVOID ELECTRICAL SHOCK, BE SURE ELECTRICITY IS TURNED OFF AT ELECTRICAL PANEL
BOARD BEFORE WIRING. Connect grounding lead to grounding lug provided. All electrical work and materials must
comply with the National Electric Code (NEC), the Occupational Safety and Health Act (OSHA), and all state and local
codes.
NOTE: Connect heater only to a branch circuit with the voltage and frequency specied on the nameplate.
Branch Circuit Connections (Power):
3-Phase Connections
Single or 3-phase power connections may be used on 240/208 volt, 5 KW models. These units come factory wired for single-phase
power but may be wired for 3-phase power by reconnecting two wires. This is done as follows:
Models with Line Voltage Control (See Figures 10 and 11):
a. Disconnect the orange wire from the junction block terminal and connect it to the orange wire on the small terminal block and,
b. Disconnect the red wire from the junction block and connect it to the terminal in the center of the block.
NOTE: Supply wires must feed direct from breaker to junction block. Thermostat wires connect to terminal board. See wiring diagram.
1. Wiring compartment access door is hinged. To open, turn single screw on the side
until the door swings away from the heater (See Figure 9). Do not try to remove screw.
2. A knockout is provided in the back of the unit for eld wiring (See Figure 9). This is
a multiple diameter knockout. Use the diameter that ts the required conduit size.
3. A grounding lug is provided near the junction block for eld wiring. The grounding
lug should be connected before any other connections.
4. The junction block is equipped with box terminals sized to accept the correct power
supply wire. Wire rated at 600 volts and 75˚C is satisfactory for branch circuit con-
nections. Either copper or aluminum conductors may be used. NOTE: the center box
terminal on the three pole junction block is used only for 3-phase operation.
5. Each heater has a wiring diagram on the inside of the access door. Consult this
diagram before making any eld connections.
Control Voltage Wiring
1. A knockout is also provided in the back of the unit for control wiring. This knockout is sized for 1/2” conduit (See Figure 12).
2. Thermostat wire shall be as follows:
Line voltage control: Use NEC Class 1, 600V, 90˚C, AWG #10 wire with copper conductor or same gauge wire as supply line.
3. Install wall thermostats in accordance with the installation instructions supplied with the thermostat.
NOTE: Do not locate thermostat in an area exposed to unusual temperature conditions or poor air circulation.
Figure 9
Figure 10 Figure 11
CAUTION – READ THESE INSTRUCTIONS CAREFULLY WHEN USING ALUMINUM WIRING
1. Carefully strip insulation from aluminum conductors and coat ends of conductors with suitable corrosion inhibitor (“Pen-
trox A” or equivalent).
2. Wire brush aluminum surface, removing corrosion; re-coat with corrosion inhibitor.
3. Connect aluminum wiring and tighten connection securely. CAUTION: Do not exceed pressure needed for making a
typical copper connection.
4. Coat entire connection with inhibitor.
5. All connections using aluminum conductors should be periodically re-checked for tightness.
6. NOTE: DO NOT JOIN ALUMINUM CONDUCTORS DIRECTLY TO COPPER.
DUAL RATED 240/208 VOLT MODELS: All 240 volt models may be operated at 208 volts with a corresponding reduction
in output.
NOTE: Line voltage control model of 5KW rating that is 208 and 240
volt, wired for 3-phase operation, should not be used with a wall ther-
mostat.
This model comes factory wired for single phase. When this model
is converted in the eld to 3-phase, control hookup should be provid-
ed by a CEK-TB2 (built-in thermostat). A 2-stage or modulating wall
thermostat can be used if hooked up correctly and according to wiring
diagram.
4. Connect the thermostat wires to terminals H1 and P1 as shown in
Figure 12. On 240 volt, single-phase model with line voltage control,
install jumpers as shown in Figure 12.
Figure 12
Hinge
Access
Door
Control
Wiring
Knockout
Power
Wiring
Knockout
Turn Captive Fastener
Knockout Locations
BACK
Heater Elements
Line Voltage
Control Models
(Single Phase):
Install Jumpers
between H
1
and H
2
and P
1
and P
2
on
208/240V units (not
dashed lines)
Connect Ther-
mostat Wires
to P
1
and H
1
Control Terminal Board
Thermostat wiring connections
- - - - denotes optional equipment
BACK
FRONT
To Thermostat
Page 5