Type EXR50


The EXR50 is a so-called voltage monitor. By means of an in-built microcontroller, the on-board electrical network voltage is permanently monitored. As soon as the charge status of the vehicle battery becomes critical, the EXR50 automatically disconnects the load. This ensures that the vehicle battery is not discharged by comfort consumers such as a cool box, fan, coffee machine, laptop, smartphone, etc. to such an extent that the engine can no longer start.

  • Continuous monitoring of the on-board electrical voltage.
  • No vehicle breakdowns due to weak batteries
  • 12 V version for passenger cars and 24 V version for trucks

This voltage monitor is suitable for standard automotive relay sockets to ISO 7588 (ISO MINI). With its mechanical contact system, the EXR50 is designed for continuous currents of 10 A, 30 A and 40 A.

Voltage rating DC 12 V
DC 24 V
Continuous current 10 A
30 A
40 A
Physical isolation of load circuit 2 (1 x NO, 1 x NC)
Temperature range -40 °C … +85 °C
Mounting method standard automotive relay socket
Design Cubic enclosure 30 mm x 30 mm x 40 mm
Feature Electronic voltage monitor that continuously monitors the on-board voltage with the aid of a microcontroller and can switch off and on loads independently.
Contact system type mechanical


  • Agricultural and forestry machinery
  • Bus: Transit and School
  • Construction machinery
  • Heavy truck

Scopes of applications

On-board electrical network monitoring with the aim of ensuring that there is always sufficient battery voltage for the starter.


Datasheet & Explanations