Higher starting load for self-regulating heating cables
Higher starting load for self-regulating heating cables
A special feature of self-regulating heating cables is the increased energy consumption at the start of heating.
The heating element in a self-regulating cable is a graphite matrix. Thanks to the semiconducting graphite matrix, the self-regulating cable has gained its main advantage, the ability to change its heat output depending on the ambient temperature.
When the ambient temperature decreases, the graphite molecules change, the resulting change in resistance causes the semiconductor matrix to generate more heat.
As the temperature rises, the opposite process occurs, i.e. heat generation is reduced.
In this case, the change of cable heating is localised, if one part of the cable is in the cold outside and another part of it in a warm room, the cable will be heated in different sections according to the surrounding temperature. The power consumption increases as the heat generated increases.
Each manufacturer of self-regulating heating cables has cable selection tables for inrush current and length.
Since the heating cable is completely cold when switched off, for the first few minutes the power consumption will be two to three times the rated power. The power consumption at start-up depends on the cable rating, the cable manufacturer, and the ambient temperature during start-up. If the circuit breaker or length of heating cable is incorrectly selected, especially when switched on at low temperatures, the cable may not start at all.
After start-up and gradual heating of the cable, the consumption is reduced to the rated consumption and may even decrease if the cable is under thermal insulation. In cases where the cable is exposed to low temperatures or cold water, its wattage may consistently exceed the rated wattage, which can negatively affect the life of the heating cable.
Higher starting load for self-regulating heating cables
A special feature of self-regulating heating cables is the increased energy consumption at the start of heating.
The heating element in a self-regulating cable is a graphite matrix. Thanks to the semiconducting graphite matrix, the self-regulating cable has gained its main advantage, the ability to change its heat output depending on the ambient temperature.
When the ambient temperature decreases, the graphite molecules change, the resulting change in resistance causes the semiconductor matrix to generate more heat.
As the temperature rises, the opposite process occurs, i.e. heat generation is reduced.
In this case, the change of cable heating is localised, if one part of the cable is in the cold outside and another part of it in a warm room, the cable will be heated in different sections according to the surrounding temperature. The power consumption increases as the heat generated increases.
Each manufacturer of self-regulating heating cables has cable selection tables for inrush current and length.
Since the heating cable is completely cold when switched off, for the first few minutes the power consumption will be two to three times the rated power. The power consumption at start-up depends on the cable rating, the cable manufacturer, and the ambient temperature during start-up. If the circuit breaker or length of heating cable is incorrectly selected, especially when switched on at low temperatures, the cable may not start at all.
After start-up and gradual heating of the cable, the consumption is reduced to the rated consumption and may even decrease if the cable is under thermal insulation. In cases where the cable is exposed to low temperatures or cold water, its wattage may consistently exceed the rated wattage, which can negatively affect the life of the heating cable.
