Trane CNT-SVX07C-EN, Zone Controller, N512 manual Timed override control, Occupied bypass mode

Models: Zone Controller CNT-SVX07C-EN N512

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Timed override control

The fan will run as configured (continuous or cycling) for occupied mode. The controller always uses the stored default setpoint values (config- urable using the Rover service tool), regardless of hard-wired or commu- nicated setpoint values. In addition, the outdoor air damper uses the Economizer Occupied Standby Minimum Position setpoint to reduce the ventilation rate.

Occupied bypass mode

The controller is placed in occupied bypass mode when the controller is operating in the unoccupied mode and either the timed override ON but- ton on the Trane zone sensor is pressed or the controller receives a com- municated occupied bypass signal from a BAS. In occupied bypass mode, the controller maintains the zone temperature based on the occupied heating or cooling setpoints. The fan will run as configured (continuous or cycling). The outdoor air damper will close when the fan is off. The con- troller will remain in occupied bypass mode until either the CANCEL but- ton is pressed on the Trane zone sensor or the occupied bypass time (configurable using the Rover service tool) expires. The temperature set- points can be local (hard-wired), communicated, or stored default values (also configurable using the Rover service tool).

Timed override control

If the zone sensor has a timed override option (ON/CANCEL buttons), push- ing the ON button initiates a timed override on request. A timed override on request changes the occupancy mode from unoccupied mode to occu- pied bypass mode. In occupied bypass mode, the controller controls the zone temperature based on the occupied heating or cooling setpoints. The occupied bypass time, which resides in the Tracer ZN521 and defines the duration of the override, is configurable from 0 to 240 minutes (default value of 120 minutes). When the occupied bypass time expires, the unit transitions from occupied bypass mode to unoccupied mode. Pushing the CANCEL button cancels the timed override request. A timed override can- cel request will end the timed override before the occupied bypass time has expired and will transition the unit from occupied bypass mode to unoccupied mode.

If the controller is in any mode other than unoccupied when the ON but- ton is pressed, the controller still starts the occupied bypass timer with- out changing the mode to occupied bypass. If the controller is placed in unoccupied mode before the occupied bypass timer expires, the controller will be placed in occupied bypass mode and remain in that mode until either the CANCEL button is pressed on the Trane zone sensor or the occu- pied bypass time expires.

CNT-SVX07C-EN

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Page 47
Image 47
Trane CNT-SVX07C-EN, Zone Controller, N512 manual Timed override control, Occupied bypass mode