WARNING:
Hazard of Electric Shock. Any installation
involving electric heaters must be grounded to earth
to eliminate shock hazard.
1.
Be sure line voltage matches heater voltage (on nameplate).
2.
Electric wiring to heater must be installed in accordance with
local and National Electrical Codes.
3.
Power controllers
must
be used when heaters are rated 3 phase
and when the heater amperage exceeds to rating of the thermostat.
4.
Refer to Wiring Diagram Table B, for the proper wiring diagram
for connecting heater.
Wiring Diagrams - Table B
WIRING
INSTALLATION
3.
Whether vertically or horizontally, the heater should be rigidly
mounted so that vibration is at a minimum since excessive
vibration will result in erratic thermostat operation. The
NWHO-6 is provided with mounting lugs to support the heat-
ing chamber. (See photo.)
4.
By using a slotted mounting assembly on either of the lugs,
the heater chamber will be permitted to expand with increas-
ing temperature.
5.
DANGER:
Hazard of Fire.
Provide minimum of 6” spacing
from chamber and related piping to nearest combustible material.
Avoid operation of heater near combustible fluids or in com-
bustible vapor or gas laden atmosphere. NOTE: Contact factory
for heaters suitable for use in hazardous locations.
6.
Provide adequate space at terminal end to permit withdrawal
of the heater from chamber should servicing be required.
Model
240V, 240V,
480V,
480V,
1ø Fig.
3ø Fig.
1ø Fig.
3 ø
Fig.
NWHO-61215
–
2
–
5
NWHO-61515
–
2
–
5
NWHO-62015
–
3
–
5
NWHO-62515
–
3
–
5
NWHO-63015
–
3
–
5
NWHO-60825
1
2
4
5
NWHO-61025
–
2
–
5
NWHO-61225
–
2
–
5
NWHO-61525
–
2
–
5
NWHO-61825
–
2
–
5
Note:
Use wire size and type specified by N.E.C. 480V and 550V heaters require 600V wire,
per N.E.C. Contactors and wire supplied by customer.
Thermostat
Line
Contactor
120V, 240V
Contactor
Thermostat
120V, 240V
L1
L2
L3
Thermostat
Line
Contactor
120V, 240V
Contactor
Thermostat
L1
L3
L2
120V, 240V
Contactor
Contactor
Thermostat
1L1
1L2
1L3
2L1
2L2
2L3
120V
or
240V
Figure 3 – NWHO6
240V, 2-3ø
Figure 2 – NWHO6
240V, 3ø
Figure 1 – NWHO
240V, 1ø
Figure 5 – NWHO6
480V, 3ø
Figure 4 – NWHO6
480V, 1ø
Note:
Dotted lines indicate “customer furnished.” However, Thermostat could have been furnished by Chromalox if so specified on the order.
