Can anyone tell me what type/standard do PTC thermistors follow commonly found in motors in the UK. Also, is there a calculator available online or for download for these thermistors. I have a submersible pump and the resistance is measured at 148 Ohms. I assume there are three thermistors in the motor connected in series. I would like to know the winding temperature from measuring thermistor resistance, not just for this pump, but for all motors with thermistors at our sites. TIA