GFS Power

Power Timer

Power Timer


Eliminate dead vehicle batteries caused by power drain from radios and data terminals that must operate while the engine is off. Allows use of accessory loads per programmed time limit while preserving battery for engine start.

  • Programmable disconnect time limit, 15 minutes to 8 hours, so that you can match your auxiliary load use to battery capacity, providing maximum run time yet still ensuring adequate reserve for engine start
  • Prevents dead batteries due to accessories being left on and forgotten
  • Once power off circuit is activated, power to auxiliary circuits is automatically restored when engine started, no delay in use of equipment
  • Low and High Voltage Disconnect
  • Simple 3 wire installation:1) Power in from battery, 2) power out to loads, 3) chassis ground. Optional ignition sense wire resets power on without having to start engine
  • Rugged construction, plastic case with epoxy potted components, designed to withstand heat and vibration of engine compartment applications, and perform in demanding emergency vehicle applications
  • 30 amp rating: Power timer can be applied to multiple auxiliary loads/circuits. Multiple devices can be left on during emergency calls without running engine

Ordering information:

  • TMR-30N

Timer Circuit Configurations

  • Range: 15 min – 8 hours
  • Increments: Minutes: 6, 15, 18, 24, 30, 45 Hours: 1, 1.5, 2, 3, 4, 8
  • Programming: Dip switches on top of unit Ignition sense input restores power after time out sequence


  • Rating: 12V nominal, 30Amps, 3mA standby current
  • Protection: Low and high voltage disconnect
  • Low < 10.5V with 10 second delay
  • High < 10.5V with 3 second delay
  • Operating Temperature: -20 to +80° C


  • Case: High impact and temp rated plastic case with epoxy potted components

LED’s Indicate Output Status

  • Present, Ok
  • Present, On Timer
  • Disconnected, Timed Out
  • Disconnected, Low Voltage



  • + DC
  • - DC
  • Ignition sense


  • + DC to loads
Model Dimensions (Inches) Weight
TMR-30N 1.25 4.25 2 1

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