Primary States (Occupancy Mode Determination) - Johnson Controls - Metasys - LIT-12011147 - Software Application - Controller Configuration Tool - 15.0

Controller Tool Help

Brand
Johnson Controls
Metasys
Product name
Controller Configuration Tool
Document type
User Guide
Document number
LIT-12011147
Version
15.0
Revision date
2022-11-18
Language
English

The Effective Occupancy is determined based on four inputs: Occupancy Schedule, Occupancy Sensor, Temporary Occupancy, and Occupancy Override.

The Occupancy Override has the highest priority in the Decision Table. If the Occupancy Override is Occupied, Unoccupied, or Standby, the Effective Occupancy is set to that value. The Occupancy Override can also be set to Bypass or Not Set. When the Occupancy Override is set to Bypass, it does not directly set the Effective Occupancy, but may trigger the Bypass Timer as described as follows.

The Bypass Timer has the second highest priority in the Decision Table, but is allowed to operate only if the Occupancy Schedule is not equal to Occupied (that is, it is equal to Standby, Unoccupied, or Not Set). The Bypass Timer is reset if the Occupancy Schedule becomes equal to Occupied and is prevented from restarting as long as the Occupancy Schedule remains equal to Occupied. The Bypass Timer also is reset if the Occupancy Override is set to a value other than Bypass or Not Set.

When the Occupancy Schedule is not equal to Occupied, if either the Occupancy Override is Bypass or if the Occupancy Override is Not Set and the Temporary Occupancy input is Active, the Bypass Timer is started for the Bypass Time. When active, the timer restarts when the Occupancy Override is Not Set and the Temporary Occupancy input changes from Inactive to Active or when the Occupancy Override changes from Not Set to Bypass. The Bypass Timer is allowed to continue timing if the Occupancy Override is set to Not Set.

The Bypass Time is user configurable. If the Bypass Timer is active and the Bypass Time is changed, the Bypass Timer is restarted for the new Bypass Time.

The Occupancy Schedule has the third highest priority in the Decision Table. If the Occupancy Schedule is Unoccupied or Standby, then the Effective Occupancy is set to that value. If the Occupancy Schedule is Occupied but the Occupancy Sensor indicates no one is present (that is, value is Unoccupied), then the Effective Occupancy is set to Standby to conserve energy. Otherwise, the Effective Occupancy is set to Occupied.

The Occupancy Sensor has the lowest priority in the Decision Table. If the Occupancy Schedule is Not Set, the Occupancy Sensor directly sets the Effective Occupancy. Finally, if all of the inputs are Not Set and the Bypass Timer is False, then the effective Occupancy Mode is set to the Default Occupancy property (initially equal to occupied).

Table 1. Occupancy Mode Determination Decision Command Hierarchy

Occupancy Override

(Supervisory Override Command)

Temp Occupancy

(Bypass Timer)

Occupancy Schedule

(Supervisory Command)

Occupancy Sensor

(Hardware Sensor)

Effective Occupancy

(Effective Occupancy Result)

Occupied

*

*

*

Occupied

Unoccupied

*

*

*

Unoccupied

Standby

*

*

*

Standby

Bypass or Not Set 1

True

Occupied 2

*

Occupied2

NOT Occupied 3

*

Bypass

False

Occupied

Occupied

Occupied

Not Set1

Occupied

Unoccupied

Standby

Unoccupied

*

Unoccupied

Standby

*

Standby

Not Set1

Occupied

Occupied

Unoccupied

Unoccupied

Not Set1

Default Occupancy 4

1 Input is set to be Not Set by default when no value has been written to it following a reset. This would typically mean that the input does not have any value assigned and it is represented by this value Not Set.
2 When the Occupancy Schedule is set to Occupied, the Bypass Timer is reset. For that reason, this row in the table is never active (the output of the Bypass Timer is reset to False before this table is evaluated following the Occupancy Schedule transition to Occupied). It is shown to avoid the potential confusion that could be caused if one of the combinations of the inputs was not handled in the Decision Table logic.
3 This entry indicates that this row is selected when the input is Unoccupied, Standby, or Not Set.
4 Default Occupancy is initially set to Occupied but the user can change the value.