WIRING
ELECTRIC SHOCK HAZARD. Disconnect all power
before installing or servicing heater. Failure to do
so could result in personal injury or property dam-
age. Heater must be installed by a qualified person
in accordance with the National Electrical Code,
NFPA 70.
ELECTRIC SHOCK HAZARD. Any installation involving
electric heaters must be performed by a qualified per-
son and must be effectively grounded in accordance
with the National Electrical Code to eliminate shock
hazard.
1.
Electric wiring to heater must be installed in accordance with
the National Electrical Code, International Electric code and/or
with local codes by a qualified person.
2.
When element wattages are not equal, heaters must not be
connected in series.
3.
Electrical wiring to heater should be contained in rigid con-
duit or in sealed flexible conduit to keep corrosive vapors and liq-
uids out of the terminal enclosure. If high humidity is encoun-
tered, the conduit should slope away from the heater.
4.
If flexible cord is employed, a watertight connector should be
used for entry of the cord into the terminal enclosure. Outdoor
applications require liquid-tight conduit and connectors.
5.
Bring the power line wires through the opening in the terminal box.
6.
Heaters are prewired and tagged for easy installation of elec-
trical wiring to the heater. Typical tagging of the individual circuits
of Chromalox TM industrial flanged heaters are shown in the
following tabulation:
Note:
Bussing tags are made with a non-conducting material. Please
leave in place for proper identification during wiring.
7.
Check for loose terminal connections and tighten if necessary.
Made to order items are prewired and tagged at the factory. Wiring of
made to order items may differ from those shown in the tabulation.
Carefully check voltage and phase on the heater nameplate and
select either the appropriate wiring shown above or check for the
appropriate wiring diagram in the heater terminal enclosure.
For
reference purposes, some typical wiring diagrams are shown in the fol-
lowing figures.
8.
The current carrying capacity of the power supply leads should
exceed the heater amperage by at least 25%. Be sure to consider
the ambient operating temperature and apply the appropriate cor-
rection factor to the ampacity rating of the wire. Heaters with the
same voltage and wattage may be connected in series for operation
at a higher voltage.
INSTALLATION (cont’d)
THERMOSTATS
10.
To prevent moisture accumulation in cryogenic applications
or when heater is exposed to freezing temperatures:
A.
Slope conduit away from enclosure (drip loop).
B.
Seal all conduit openings to moisture/explosion resistant
terminal enclosure.
C.
Insulate terminal enclosure.
D.
Fill thermowell(s) with silicone fluid when heater is
mounted with terminal enclosure up.
BEFORE ENERGIZING
1.
Check that the gasket is in place and the flange is securely bolted
to the tank.
2.
Check that power supply connections are made according to the
wiring diagram. Also check for positive connection of all bus bars
and power supply leads.
3.
Check all bussing hardware is tightened to 20-25 in-lbs.
4.
Check all bussing to element connections are tightened to 14-17
in-lbs.
FIRE OR SHOCK HAZARD: Moisture accumulation in
the element refractory material, element over-tem-
perature, or sheath corrosion can cause ground fault
to the element sheath, generating arcing and molten
metal. Install Ground Fault Circuit-Interrupter (GFCI)
to prevent personal injury or Equipment Ground Fault
Protection to prevent property damage.
1.
Integrally mounted thermostats are available: single throw models.
2.
Electrical rating of thermostats:
3.
Thermostats may be connected directly to heaters that are rated
within the electrical capacities specified. When the heater phase or
amperage exceeds the contact rating of the thermostat, the heater
should be controlled by a magnetic contactor with the thermostat
wired for pilot duty. Refer to the thermostat instruction sheet
packed with the heater.
4.
If optional thermostat kit is purchased, please refer to instruction
manual shipped with kit for proper bracket and thermostat mounting
5.
WARNING
: To maintain third party listing on an E4 housing, do
not add any sparking device, such as a thermostat, inside the termi-
nal enclosure.
Thermostat Type
Voltage
T1
T2
120
30 Amps
30 Amps
240
30 Amps
30 Amps
480
Pilot Duty
Pilot Duty
3
No. Circuits
Phase
Tagging
1
1
L1 & L2
1
3
L1, L2 & L3
2
3
AL1, AL2, AL3
BL1, BL2 BL3
3
3
AL1, AL2, & AL3
BL1, BL2 & BL3
CL1, CL2 & CL3
