There are many ways to write a logic to perform debounce timer. This article documents one of the many ways to write debounce timer in RSLogix 500 and RSLogix 5000. We will use the ladder logic snippet below to explain the debounce timer implementation. Lets get started…

As the pressure increases, the logic checks to determine if it is at least 300kPa (Stage 1 Suction Pressure). Once it has gone past 300kPa, “Blowdown Sequence Active” will be energized.
Even if the pressure bounces around 295kPa the “Blowdown Sequence Active” will not be deenergized.
But when the pressure goes below 290kPa, the “Blowdown Sequence Active” will be denergized.

Xybernetics Allen-Bradey RSLogix500 - Debounce Logic Deadband