IEEE-515, Standard for the Testing, Design, Installation, and Maintenance of Electrical Resistance Trace Heating for Industrial Applications, Section 8.4.
"Periodic operational checks on electric heat tracing circuits are essential for maintaining reliable, trouble-free operation of the process. It is recommended that these checks be scheduled at regular intervals depending on the importance and usage of the heat tracing to the process or plant operation. When electrical heat tracing is used for freeze protection, a major operational check should be carried out during the fall season prior to freezing conditions. All circuits and controls should be checked for proper operation. Each circuit should be checked for electrical insulation resistance, continuity or normal current flow, and properly applied voltage. All controls (thermostats, indicating lights, meters, controllers, etc.) should be checked for proper operation and indication. When the heat tracing is used for normal temperature maintenance or critical process control, an operational check should be carried out on a more frequent basis. The electrical insulation resistance and heating cable continuity should be checked after any mechanical maintenance has been performed on pipelines, vessels, or equipment that has been traced to assure the integrity of the heating cable before re-energizing. Ground-fault equipment devices should be tested periodically, whenever the heat tracing systems is energized."
- Raychem Installation & Maintenance Guide for Auto-Trace Heat Tracing Systems for Ordinary Locations.
- "For systems controlled by line-sensing thermostats, check the system at least twice a year. Systems controlled by ambient thermostats should be checked before each winter."
- Refer to yours or client's Engineering Standards (if applicable) for additional information on Commissioning & Maintenance of Electric Heat Trace Systems.