Most N2 devices do not contain a time of day clock that you can access directly. They do have an on-board clock that can be synchronized with the head end and is used as a fallback when the N2 device becomes disconncted from the head end. In normal operation they completely rely on a supervisory controller to tell them if they should be in Occupied or UnOccupied mode by toggling a binary point.

Typically, you’ll see set points for Occupied mode and another pair for UnOccupied mode. Simply have your new HMI or another (BACnet or OPC as appropriate) controller toggle the Occupied point in each N2 device to indicate the mode that you want each controller to operate in.

Check the manufacturer documentation for each N2 device and application supported by it for the correct point to toggle the Occupied / UnOccupied status of the device and the point names assigned for the set points.

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