Structure and inner electrical connection: Notes

Resistors with a positive temperature coefficient (PTC) are designated as PTC resistors. The warmer the PTC becomes, the higher its resistance. With a PTC, high current flows at switch on, for example. With increasing heating, this level of current falls. Metals are PTC conductors. Their resistance increases with rising temperature.

Fig 1: Heating Element For Engine Ventilation Heating - Circuit Diagram

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