A thermal sensor embedded in the elevator traction motor windings that monitors temperature and triggers protection on overheating.
Full Definition
Motor temperature sensors (typically PTC thermistors, PT100 RTDs, or thermocouples) are embedded in the stator windings of the traction machine during manufacture. They continuously monitor winding temperature and send signals to the drive controller or safety relay. When temperature exceeds the preset trip threshold (typically 130–155°C for class F insulation), the drive shuts down the motor to prevent insulation damage and winding burnout. A warning threshold (typically 10–15°C below trip) enables reduced-speed operation or increased maintenance inspection frequency. Motor temperature monitoring is required by EN 81-20 via the drive's protective functions and is essential for extended motor life in high-use elevators.
