Assignment Strategies

Guidelines

-Equipment items can have any number of equipment actions

-Equipment items can have actions stemming from any number of device interfaces

-Equipment items can have multiple actions with the same event trigger, and not every event trigger must be used

-Equipment items cannot have actions commanding the same points targeted by actions on other equipment items unless they have different command priorities.

-Equipment items cannot have two actions with parallel single-action triggers (e.g. Event Start/ Event Stop) commanding the same point when one dual-action trigger will suffice (e.g. Event Start/Stop)

Once defined, Events2HVAC uses equipment actions in conjunction with information from your event provider to execute commands targeted at the associated physical equipment at the appropriate times.  Examples include starting/stopping an AHU, setting the temperature to an occupied setpoint, setting a room VAV box to occupied or unoccupied modes, turning on or off lighting in a room, etc.

There is no limit to the number of actions that can be defined on a single equipment item. Further, within an equipment item, multiple actions can be defined for the same event trigger, and actions from different device interfaces can be mixed. For example, from a single equipment item, you could send a start/stop command via a BACnet interface and send an off/on command to a different lighting control interface.

You should NOT use the same device end point in an action in multiple equipment items, however. Unpredictable results may occur in the command output to that point if it is receiving event data from different equipment items. Each equipment item generates its own optimized schedule for commands, and this information is not shared between equipment items.

Given this flexibility available in assigning actions, care should be exercised when creating equipment actions to ensure correct results. The most important aspect of equipment actions to consider, apart from the device command itself, is the event trigger chosen. As detailed in the Concepts document, each event trigger corresponds to a point in an event, for example the start of pre-event setup, the start of the event itself, etc.

While there is a trigger available for each individual point (single-action triggers), there are also triggers which associate two parallel points in an event (Start/Stop or Setup/Teardown), called dual-action triggers. Dual-action triggers should be used in all cases where two inverse commands are to be sent to a point (e.g. turning the lights, VAV, AHU, etc. on at the start of event setup and at the end of event teardown). Once again, see the Concepts section for a detailed explanation of this.