About Boolean minimum on and off times

Each Boolean writable point has built-in timers to specify minimum on and/or minimum off times.

The respective point properties are Min Active Time and Min Inactive Time. Usage is optional, and both properties work independently. Typical usage is to prevent short-cycling of equipment controlled by the point. Default property times for a Boolean writable are all zeros (00000h 00m 00s), which effectively disables a timer. In either property, you can specify any value needed using of a mix of hours (h), minutes (m), and seconds (s) to enable that timer.

A state change transition to active or inactive triggers a minimum timer. This stores the new state value in the point’s priority array (at priority level 6) for the duration of that timer. While a minimum timer is in effect, only input changes at a higher priority (5 or above) or an emergency action can affect the Out value.

For example, a Boolean writable point controls a fan, with related properties set as follows:

Starting with the fan stopped at schedule level, priority In16, if a user manually overrides using priority level In8, the fan runs for 90 seconds at priority level 6 (a higher level). After this period, the fan continues running at the override In8 level for the duration of the override.
During the initial 90 seconds, a different override action (off or auto) is ineffective because the higher priority level 6 remains in control.
Once stopped, the point’s minimum off time keeps the fan off at priority level 6 for the specified duration (for example, 3 minutes and 5 seconds). During this period, only an emergency command or input change at In2–In5 can effect further change.

About Boolean minimum on and off times

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