OPERATION
FIRE/EXPLOSION HAZARD. This heater is not intended for use in hazardous atmospheres where flammable vapors, gases, liquids or other com- bustible atmospheres are present as defined in the National Electrical Code. Failure to comply can result in personal injury or property damage.
Before energizing this heater:
1.Be sure all electrical connections are tightly made. Hold ter- minal with pliers when tightening screw.
2.Be sure that all conductors are properly insulated, and that they will not chafe at the heater wire entrance due to expansion and contraction of the heating element.
3.Be sure that all terminal covers have been properly replaced, and that secondary insulation bushings have not been omitted.
A. Controlling Radiant Intensity — Standard Radiant Heaters are built to operate at approximately 40 watts per sq. inch on the element sheath. When it is desired to reduce radiant inten- sity, one or more of the following methods may be used.
i.INPUT CONTROLLERS. These
ii.SOLID STATE POWER CONTROLLERS. For best
B.Maximum Ambient Temperatures –
Chromalox Radiant Heaters are not recommended for applica- tions in ambient temperature exceeding 450˚F. Higher ambient temperatures mean shorter heater life.
Maximum work temperature in a given time depends on sever- al factors: Reflectivity of work, specific heat of work, mass of work, kW input and losses from oven, and time of exposure. As work temperature increases, the work loses heat by radia- tion and by convection to the surrounding ambient. Although it is a general principle of Radiant Heater application that work temperature conventionally exceeds ambient temperature, in cases where extremely high work temperatures are desired, it is necessary to enclose the heaters in order to increase the ambi- ent. If evaporation of a liquid is desired as a result of increas- ing work temperature, it is necessary to provide ventilation air in order to carry away the evaporated liquid. Under carefully engineered circumstances, a maximum work temperature of 600˚F may be attained.
MAINTENANCE
ELECTRIC SHOCK HAZARD. Disconnect all power before installing or servicing heater. Failure to do so could result in personal injury or property damage. Heater must be installed by a qualified person in accor- dance with the National Electrical Code, NFPA 70.
A.To remove Heating Element –
1.Remove terminal cover screws and terminal cover.
2.Disconnect heating element from electrical leads at both ends.
3.Remove screws from porcelain terminal blocks.
4.Remove element support clips and secondary insulating bushings.
5.Lift element out of heater.
B.To Install Element —
Observe instructions for removing element and proceed in reverse fashion. Be sure to replace secondary insulating bushings.
C.Care of Reflectors —
Reflectors should be cleaned periodically. A mild soap and water solution or fine cleaning powder is best, although more drastic means may be required if reflectors are badly soiled by chemical or other deposits. The reflector is aluminum. DO NOT use alkali cleaners since alkalies will dull reflector. Mild
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