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

Table 12: TEC2664Z-2 Rooftop Controller Installer Configuration Menu (Part 5 of 5)Parameter Description and Default Selection OptionsAppearingon DisplayUnocc HT 4 If network communication is lost Range: 40.0°F/4.5°C to 90.0°F/32.0°Cwith the zone controller(s), thereturn air sensor controls the rooftopcontroller to maintain thisUnoccupied Heating setpoint.Default: 62.0°F/17.0°CSp range 6Pressure 6Sets the static pressure transducerrange.Default: 0Sets the static pressure transducersetpoint maintained by the bypassdamper.Default: 0.8 in. W.C./200 Pa(0): 0 in. W.C./0 Pa to 1.5 in. W.C./375 Pa(1): 0 in. W.C./0 Pa to 2 in. W.C./500 Pa(2): 0 in. W.C./0 Pa to 3 in. W.C./750 Pa(3): 0 in. W.C./0 Pa to 4 in. W.C./1,000 Pa(4): 0 in. W.C./0 Pa to 5 in. W.C./1,250 PaRange: 0 in. W.C./0 Pa to 2 in. W.C./500 Pa1. RTC MAC is the unique device address of the rooftop controller (from 004 to 127) on the MS/TP network.2. Local Unocc Override appears only when in the Unoccupied mode.3. When adjusting the numeric value, press the UP/DOWN arrow key to change the value by single increments; press andhold the UP/DOWN arrow key to change the numeric value in increments of ten.4. When adjusting the temperature, press the UP/DOWN arrow key to change the value in 0.5F°/0.5C° increments; press andhold the UP/DOWN arrow key to change the value in 5.0F°/5.0C° increments.5. When adjusting the temperature, press the UP/DOWN arrow key to change the value in 5.0F°/5.0C° increments; press andhold the UP/DOWN arrow key to change the value in 50.0F°/50.0C° increments.6. This value is adjustable in 0.1 in. W.C./25 Pa increments.TEC2664Z-2 Rooftop Controller Operation and StrategyContrary to low-end commercial and residential zone controllers that usetwo-position demand and no demand logic to energize heating and cooling, theTEC2664Z-2 Rooftop Controller uses PI demand to operate heating and coolingstages. In addition, accurate temperature control at the zones is achieved via aunique, time-proportioning algorithm that virtually eliminates temperature offsetassociated with traditional, differential-based zone controllers. This featureenables performances and control sequences that are much closer to what isnormally found in DDC application-specific control devices.The operation of the rooftop controller is directly related to the operation of thededicated zone controllers. Although the rooftop controller can operate in astand-alone manner if network communication is lost, normal system operationrequires that this network communication is functional.Data Exchange between the Rooftop Controller and the ZonesHeating and cooling demand is first exchanged from the zone controllers to therooftop controller. These output values are based on the PI heating weightconfiguration and the PI cooling weight configuration. Each voting zone alsocalculates its demand values based on the occupancy mode and setpoints currentlyin use: either Unoccupied, Standby, or Occupied.36TEC Zoning Control System for Stand-Alone and BACnet® MS/TP Networked ApplicationsTechnical Bulletin