INSTA PTC Thermistors are manufactured in accordance with DIN 44081 and 44082. Due to their small thermal mass, they have favorable temperature sensitivity.
INSTA PTC Thermistors should be placed as near as possible to the hot spot: In three phase motors, one Thermistor should be embedded in each phase. Good thermal coupling between Thermistor and winding is essential. The PTC Thermistors should be inserted parallel to the winding. The resistance increases sharply in the region of the nominal response temperature
In this way the mechanical stresses on the PTC Thermistors during forming the end turns of overhang winding can be minimized. Shrink cap is especially well suited for this because of its mechanical stability. Response times ≤ 5 sec. are achieved with INSTA PTC Thermistor.
