TEC Zoning Control System for Stand-Alone and BACnet® MS/TP ...

When the fan output is off (Terminal G), the static pressure control loop is also offand the bypass damper is fully open to the 10 VDC output. This conditionminimizes the air pressure related noise during initial fan startup. Be aware that thefan is always on during occupied periods, and that it only cycles on demand withthe heating and cooling stages during unoccupied periods.When the fan output is on (Terminal G), the static pressure control loop is enabledand the bypass damper modulates to maintain the desired static pressure setpointbased on the static pressure input reading at the rooftop controller. Use the ManualScroll Display feature at the rooftop controller to locate the Pressure parameterand determine the current static pressure value.Sequence of OperationTEC2647Z-2 and TEC2647Z-2+PIR Zone ControllersThe sequence of operation is determined by the Johnson ControlsTEC2664Z-2 Rooftop Controller mode and the configuration parameterspreselected for the zone controller; see TEC2664Z-2 Rooftop Controller on page43 for more information. See Figure 7 through Figure 16 for sequence of operationexamples.PIR Occupancy Sensor OperationThe zone controller is available with or without a factory-installed PIR occupancysensor cover. A zone controller equipped with the PIR occupancy sensor coverprovides advanced active occupancy logic that automatically switches occupancylevels from occupied to standby as required, when motion is sensed. This featureresults in incremental energy savings during scheduled occupied periods when thespace is unoccupied. This allows zones, such as conference rooms and storagerooms, that are infrequently occupied to use relaxed setpoints during most of theiroccupied period when the space is not being used.The aim of using a standby setpoint is to have the system recover fairly quicklybetween the standby and occupied setpoints when motion is detected in the zone.The relaxed value of the standby setpoint must be far enough from the occupiedsetpoint to warrant the energy savings of a PIR occupancy sensor coverinstallation, but close enough for the system to recover quickly to ensureoccupancy comfort.To enable the advanced occupancy logic, the following must be set at the zonecontroller:• If a local PIR occupancy sensor cover is installed, the PIR Func parametermust be set to on.• If a remote PIR occupancy sensor is attached to BI1, the BI1 parameter mustbe set to MotionNO or MotionNC.42TEC Zoning Control System for Stand-Alone and BACnet® MS/TP Networked ApplicationsTechnical Bulletin