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Debounce: Eliminate extra on/off transitions

that occur when using mechanical buttons and switches

When a switch or a pushbutton has to be connected to a digital circuit it is often (almost always) a nasty thing, because its unwanted behaviour.

It is a common practice to connect a button or a switch to a digital system (to a microcontroller, to a PLC, or to a PC).

If we measure the voltage at the input of the ACE PLC with an oscilloscope, it would show the following graph.

Debounce can be accomplished without programming.

 

Go to the Tags tool.  The Input Bits now has the option to set the Debounce length from 0-250 ms.

Thats it.  In most cases, you’re done and there is no need to continue farther.