At a Glance

  • System Fail-Safe
  • "Loss of Control" Detector
  • Dry Contact Relay Output
  • M and SM, and 70M I/O Rack Compatiblity
  • 5 Volt Logic
  • 3-Year Limited Warranty
  • 2 Second Timeout
  • Negative Edge-triggered
  • Fail-OPEN output
  • User-specified Timeouts
  • Adjustable Timeouts 
  • Fail-CLOSED Output - 0.5 Amp 10VA
  • Customize It! IPD is glad to quote your specific custom module


Brentek's M-WDT5 and SM-WDT5 Watchdog Timer Modules monitor a control system’s activity by detecting on/off transitions of a control line. During normal system 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, 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 M-WDT5 and SM-WDT5 Watchdog Timer Modules use patented timing technology to monitor control system integrity. The output is a dry contact relay which is rated at 1 Amp resistive (20VA) and is configured to Fail-OPEN.  The WDT5 provides direct plug-in compatibility with the Industry-standard "Mini"  M-Case (M, 70M) and the "Small" S-Case - both are 0.4" thick and afford a very compact footprint.   

In a recent product enhancement, adjustable timeouts (0.075-5 sec. or 2-8 sec.) are now available for these watchdog timers.  They are also available with a customer-specified fixed timeouts in the range of 0.1 - 60 seconds.  These watchdog timers come standard with a 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).  

The Brentek M-WDT5 Watchdog Timer is available from IPD, Inc. on  The M-WDT5 is available from IPD, Inc. on Amazon.


How to Purchase Customize It!