What Is a Watchdog?

What’s a watchdog? We’re not talking about a loud, scruffy anti-social canine. We’re talking about a watchdog circuit. A watchdog and a watchdog circuit do have something in common, however. They serve the common purpose of searching for things that are out of the ordinary.

What does a watchdog do?

In an ideal world your processor never fails, and your software never crashes. Unfortunately, we don’t live in an ideal world. That’s why we have watchdogs.

A watchdog circuit, also known as a watchdog timer or simply WDT, monitors code and resets the processor in the event of a software error. The watchdog circuit helps detect errors and helps recover your system in the event of a crash.

The watchdog timer resets at normal intervals so that it does not time out. This reset is known as kicking.

“Kicking the watchdog” is a good thing. Every time the watchdog circuit kicks, or the timer restarts, the system continues operating as normal. If the circuit does not kick, this means that something is wrong. This normally puts the system into a safe state and restores normal system operation.

Indramat watchdogs

Some Indramat systems use a watchdog circuit. Systems that operate with an Indramat CLC control, for example, use a watchdog timer.

The CLC watchdog refreshes every 100 milliseconds. If you see a decimal point on your control display, that means the watchdog circuit is active.

The watchdog is your last resort rather than your primary protection. Again, these circuits only activate when something appears to be wrong with your system.

Give us a call if your Indramat watchdog timer doesn’t kick, or if you have any problems with your Indramat motion control system. We have the knowledge and experience to get your system up and running again as soon as possible. Call 479-422-0390 for immediate Indramat support.