Inherently Temperature-Safe cables are cables that have no significant output at their withstand temperature. More

The maximum temperature a heating cable can be exposed to before it is damaged. Sometimes referred to as maximum exposure temperature or design temperature

The surface of the heating cable must not exceed the maximum temperature of the constructional materials or the Temperature Classification if installed in a hazardous area. This is ensured by limiting the pipe or workpiece temperature to a safe level either by design calculation or by means of temperatue control devices.

Constant Wattage cables do not regulate they have the same output irrespective of pipe or surface temperature

RTD Sensor (DRTD)