FIRE HAZARD. Failure to comply with the following
could result in personal injury or property damage.
A. Do not operate heaters at voltages in excess of that marked on
heater since excess voltage can shorten heater life.
B. Do not operate heaters under conditions that result in sheath
temperatures higher than the recommended maximum since
excess temperatures can cause premature failure and fire.
Generally, sheath materials are limited to the following maximum
temperatures.
The table above applies to ring, tubular and cartridge element as well
as most strip elements.
A.
Chrome Steel Finned Strips — 950˚F.
Heaters should not be operated in environments with factors that
can destroy the integrity of electrical insulation inside the heater. The
following contaminants and others can create current leakage (shock)
hazards, permanent heater damage, or cause heater failure and there-
fore, should be avoided.
A.
Water or water vapors
C.
Corrosive liquids and vapors
B.
Grease, oil or oil vapors
D.
Noxious or reactive gases
Low Megohm Condition
— The refractory material used in elec-
tric heaters may absorb moisture during transit, storage or when sub-
ject to humid environments that will reduce the cold insulation resis-
tance (low megohm). Low megohm may result in a high leakage cur-
rent to ground and nuisance trips of ground fault protection equip-
ment. Normally, the megohm value increases after heat-up. Typical
insulation values are 5 megohm or greater on complete assemblies or
20 megohm on individual unsealed elements. It is recommended that
heaters with 1 megohm or less be dried out before applying full power.
If dried properly, low megohm will not effect heater life or efficiency.
To correct a low megohm condition, remove terminal enclosure
cover, gaskets, and terminal hardware. Bake heaters in an oven at 300
to 500˚F for several hours or preferably overnight.
An alternate procedure is to cycle the heater in 10 to 15 minute
periods at low voltage until megohm values are normal. Sheath tem-
peratures should not exceed 350˚F.
NOTE:
Low megohm on heating elements with epoxy or hermetic
seals cannot be serviced in the field. Typical resistance
values when sealed are 200 megohm or greater.
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 Protection to prevent
property damage.
103 GAMMA DRIVE, PITTSBURGH, PA 15238
Phone: 800-443-2640 www.chromalox.com
OPERATION
Sheath Material
Maximum Sheath Temperatures
Copper
350˚F
Iron or Steel
750˚F
Chrome or Stainless Steel
1200˚F
INCOLOY
®
1500˚F
MONEL
®
900˚F
WIRING
HAZARD OF ELECTRIC SHOCK. Any installation
involving electric heaters must be effectively ground-
ed in accordance with the National Electrical Code to
eliminate shock hazard.
1.
Electric wiring to heating elements must be installed by a quali-
fied person in accordance with the National Electrical Code or
local electrical codes.
2.
Type and temperature rating of wire should be suitable for appli-
cation.
Limited Warranty:
Please refer to the Chromalox limited warranty applicable to this product at
http://www.chromalox.com/customer-service/policies/termsofsale.aspx.
