TDD TUD Series OFF-Delay Relay Output

The TDD TUD Series OFF-Delay Relay Output from the ATC Diversified Electronics division of Marsh Bellofram is a family of rugged, high-reliability OFF-delay relay outputs, designed to equip industrial machinery, conveyor belts, exhaust fans, heating systems, lubricators, and pump and motor controls with timed sequence delay, soft-start delay or auto-start functions for added machinery and equipment protection.Voltage is continuously applied to the input.

An external isolated switch controls the timer. When closed, the relay energizes. Opening the switch initiates the delay period. Upon completion of the delay period, the relay de-energizes. If the control switch recloses during the delay period, the relay remains energized and the timer resets to zero.



  • OFF-DELAY timing mode
  • Choose from multiple standard ranges
  • Optional lock nut, knob or fixed time adjustment
  • Plug-in style enclosure


  • Industrial machinery and equipment
  • Conveyor belts
  • Exhaust fans
  • Heating systems
  • Lubricators
  • Pump and motor controls
  • Flashing light control
  • Engine auto start control