Insta control pvt. Ltd. Is the manufacturer and exporter of ptc thermistors. These thermistors are manufactured in accordance with din 44081 and 44082. These are to be embedded in each phase. Good thermal coupling between thermistor and winding is essential. The ptc thermistors are to be inserted parallel to the winding. The resistance increases sharply in the region of the nominal response temperature. A shrink cap is especially well suited for this because of its mechanical stability.