Heat-Tracing Systems for Hazardous Division 1 Locations

5.7 Thermal Insulation Requirements5.7.1 Preinsulation ChecksVisually inspect the heating cable and components for correct installation and damage. Refer to Section 6.2,Troubleshooting, for a summary of symptoms, possible causes, and recommended corrections.5.7.2 Insulation Installation HintsCorrect temperature maintenance requires dry thermal insulation, properly installed.Check insulation type and thickness against the design specification, or consult Raychem productliterature for insulation data.Check that all pipework—including fittings, wall penetrations, and other areas—has been completelyinsulated.Insulate as soon as possible after tracing to prevent heating cable damage.5.7.3 MarkingMark the location of heating cable components on outside of insulation.Install “Electric Traced” labels along piping at 10-foot (3-meter) intervals on alternate sides.5.8 Thermostat ControlsFollow the installation instructions supplied with the thermostat. Use the proper wiring diagram for theheating cable layout and control method desired. Wire the thermostat using the normally closed (NC)terminals so that the contacts close with falling temperature.35