Chromalox PG412-10 specifications Installation cont’d, Wiring

INSTALLATION (cont’d.)

5.Reflector Spacer Sheets — Where heaters are not mounted side by side (see Fig. 2), reflector spacer sheets can be used between heaters. These reflector spacer sheets and companion reflectors consisting of an extruded aluminum housing with reflector sheet and mounting clamps are available. Check factory.

FIRE HAZARD: Since Radiant heaters are capable of developing high temperatures, extreme care should be taken to:

A. Keep combustible materials at least 6” away form sides and back of heater housing and its supporting brackets and spaced far enough in front of heater (heating element side) so thermal radiation from the elements will not ignite com- bustible materials.

B. If combustible materials are being processed, stoppage of process should initiate immediate heater shutdown and interception of residual heat from radiant heaters (use radiation baffles or move heaters away from work).

C. In the case of solvents of an explosive nature, ventilation air must be in sufficient volume to dilute the solvent vapor so that explosive mix- tures cannot occur, refer to NFPA 86, Standard for Ovens and Furnaces.

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 or serviced 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 person and must be effectively grounded in accordance with the National Electrical Code to eliminate shock hazard.

1.Electrical connection to the Radiant Heater is made through two openings tapped for 1/2” connector. Openings are in the top of the extruded heater housing, one near each end.

2.Access to Radiant Heater terminals is obtained by removing the two screws in each of the terminal box covers.

3.Wiring should be run in flexible or rigid metal conduit and must be installed in accordance with the requirements of the National Electric Code and such other local requirements as may be applicable.

4.Wires supplying power to heating element terminals shall have insulation rated for 150°C minimum.

High Temperatures will oxidize copper. Use only nickel- plated copper wire for supplying power to heater. Do not use aluminum conductors.

Figure 3

5.A sufficient length of high temperature wire (not less than 12” should extend from heater terminals to a remote connection box whose location involves normal room temperatures there- by permitting use of normal electrical wiring to that point.

6.Leave loop of wire in heater terminal box to allow for expan- sion movement of heating elements.

7.Assemble terminal, screw, saddle clamp and wire as shown in Figure 3.

8.Hold terminal with pliers and tighten the terminal screw securely with a screwdriver.

9.Single End. Parallel Wiring (Fig. 4A) Power wiring enters heater through either of the 1/2” tapped openings in heater housing. Wiring to opposite end is conveyed through wire-way provided behind integral reflector in housing extrusion. High temperature wire must be used; maximum wire diameter (over insulation) must not exceed 0.224”. Each element must be rated at applied line voltage.

10.Single End, Series Wiring (Fig. 4B) Power wiring enters heater through either of the 1/2” tapped openings in heater housing. Heating element terminals at opposite end are wired in series. High temperature wiring must be used. Each element must be rated at 1/2 line voltage.

External series wiring of radiant heater assemblies is not prac- tical when internal series connections can be made so easily.

Single End — Parallel	Single End — Series
Figure 4A	Figure 4B

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