At a Glance

  • Detect "Loss of Control"
  • Precise timeouts for Mission-critical Systems
  • Timeouts from 31 mSec. to 68 Minutes
  • 5, 12,15, or 24 VDC Logic
  • Crystal-based Digital Timing
  • Reset Options for Long-boot Time Controllers
  • 3 Year Factory Warranty
  • 2 second Standard Timeout
  • Fail-OPEN DRY Contact Output
  • Compatible with Classic 0.6" I/O Racks
  • Customer-specified Timeouts
  • Fail-CLOSED Output Relay
  • 5 AMP Fail-OPEN Output Relay*
  • Customize It! IPD is glad to quote your specific custom module


WDT5D Series DIGITAL Watchdog Timer Modules offer millisecond-resolution monitoring of a control system’s activity by detecting on/off transitions of a control line. During normal operation, the watchdog’s internal timer is continually reset by control line activity and its dry-contact output remains energized. When control is lost (control line stops toggling), the timer times-out and de-energizes the output contact, indicating “Loss of Control”. 

Loss of Control is caused by problems such as CPU latch-up, control system faults, wiring/cabling failure, unanticipated software conditions, peripheral failures, tampering, communications problems, or power failures. The system designer can use the watchdog timer's output contact to address Loss-of-Control by energizing an alarm, shutting down the system, or providing a reset signal to the CPU/controller.

The WDT5D series watchdog timer modules uses a crystal-based digital timer for precise timeouts (+-1%) needed by mission-critical systems.  Timeouts range from 31 mSec. to 68 Minutes in binary incrrements. In keeping with its precision nature, the WDT5D triggers on both the rising edge and the falling edge of the input - useful for dealing with asymmetrical input waveforms.  It also offers optional timeout reset features that, in conjunction with the fail-CLOSED option, are useful for resetting systems with long boot-up times such as those operating under WindowsTM.

It offers a compact footprint and direct plug-in compatibility with Industry-standard I/O racks from Brentek, OPTO 22 (G1), and Grayhill (70).  The WDT5D series is available in 4 logic voltages (5V, 12V, 15V, and 24V):

  • WDT5D
  • WDT12D
  • WDT15D
  • WDT24D

The standard timeout is 2 seconds and customer-specified timeouts are available.  These watchdog timers come standard with a highly reliable dry contact output which is rated at 1 Amp resistive (20VA) and is configured to Fail-OPEN.  Optionally, they have a Fail-CLOSED relay that is rated at 0.5 Amps resistive (10 VA) or a 5 Amp Fail-OPEN output relay. 

How to Purchase Customize It!