Classified by temperature
According to the composition of polymer PTC materials, self-controlled temperature heating cables are divided into two categories: low temperature type and high temperature type.
Self-limiting electric tropics
Self-limiting electric tropics
Common heating cables with polyolefin as the base material are 65 degree temperature grade heating cables and fluorine-containing materials as the base material 110 degree and 150 degree heating cables. THE TEMPERATURE CLASS HERE IS DEFINED AS THE MAXIMUM AMBIENT TEMPERATURE AT WHICH THE HEATING CABLE CAN BE EFFECTIVELY APPLIED. It can also be understood that the cable can be stably applied for a long time and produce the highest ambient temperature of the effective heating power output, exceeding the specified temperature level, on the one hand, due to the increase in resistance, the output power of the cable itself is very small, and the actual heating efficiency is very low. On the other hand, long-term overtemperature use will deteriorate or attenuate cable performance such as PTC characteristics, heating power, etc., which will reduce the service life and operational reliability of the cable. However, it is also possible to be intermittently exposed to temperatures above the temperature isopole for a short period of time. Therefore, in addition to the above temperature ratings, self-controlled temperature heating wires, there is another temperature class. For example, for cables with a temperature rating of 65 degree , this temperature class is 85 degree , for cables with a temperature rating of 110 degree , it is 130 degree , and for cables with a temperature rating of 150 degree , it is 230 degree . However, the effective output power of the cable is close to zero.
Gutter snowmelt heating cable
Gutter snowmelt heating cable
Due to the lack of relevant literature, many people have a wrong understanding of the temperature level of self-controlled heating cables, believing that it refers to the maximum surface temperature of heating cables, so there are 45.65, 85 and 105 degree temperature grades polyolefin heating. In fact, because the output power of the cable is related to the ambient temperature, and the surface temperature of the cable is closely related to the ambient temperature and insulation state at the time of testing. Therefore, it is unscientific and inaccurate to use the surface temperature to define the temperature level of self-regulating heating cables. We need to remember that for polyolefin-based heating cables, the maximum continuous use temperature should not exceed 65 degree C.
