PTC limit temperature sensors

PTC are used mainly for monitoring tasks, a principal application is in this case the thermal monitoring of motors, generators and transformers.

Due to the abrupt curve characteristic, PTC thermistors are not suitable for precise temperature measuring, they only serve to interrupt the power supply in a well-defined reference temperature.

PTL / PTM Series


  • Temperature sensing
  • Max. DC 16V / 30V
  • R25: 100Ω...330Ω
  • Ø 5mm / B7,5 x L15 x H4,5mm
  • Tc: 40°C...160°C
  • Ts: 55°C...180°C

MSF Series


  • Coil winding temperature sensor
  • 60°C...180°C
  • Single-, Triple or customized
  • Diameter ≤ 3mm
  • Robust PVDF-Insulation cap
  • Thermal response time ≤ 5s
  • UL approved versions available
  • Customized versions
PTC Kaltleiter Drilling

Motor protection relay


  • Suitable for PTC Thermistors according to DIN 44081 / 44082
  • 1...9 PTCs in row
  • Screw- or DIN-Rail mounting
  • Signal lights for switching state
  • Very easy to connect
  • Relay: AC 250V 6A changeover contact


α Therm


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safety components, sensor elements or sensors

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