Power Relay Assembly Sensor (PRA)


In accordance with the rapid expansion of eco-friendly vehicles, the safety of the Battery Management System (BMS) is critical. So, OEMs are monitoring the temperature of the Power Relay Assembly (PRA) to prevent fire or other dangerous conditions.

Thermometrics Power Relay Assembly (PRA) Sensor consists of high capacity relay and related electronics. It can be used in Electric (EV), Hybrid Electric (HEV) and Plug-in Hybrid Electric (PHEV) Vehicle applications. It is mounted on the BUSBAR of the PRA, through which electric current flows, to measure surface temperature of the BUSBAR.


  • Part No: BAF140B
  • R@100 = 3.3kΩ ±5%
  • B(0/100) = 3970K±2%
  • Operating Temperature Range: -40°C - 200°C
  • Insulation Resistance: >100MΩ @500V DC
  • Withstand Voltage: 2500V AC for 1 sec
  • RoHS Compliance (Directive 2011/65/EU)
  • Easy to install


  • EV/HEV/PHEV - Power Relay Assembly (PRA) Surface Temperature Measurement