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

Table 5: System Mode Calculation with Five Voting Zones (Example 3)Heat ActionVotingZone 1VotingZone 2VotingZone 3Table 5 shows that the resulting heat and cool weight used by the rooftop controllerfor the five voting zones is different, meaning different heating and cooling actionbased on the configuration of the rooftop controller. The heating or cooling actiondelivered to the zones also depends on the heating and cooling lockout functions,which are based on the outside air temperature and the supply air temperature.Overrides and Zone Controller User Interface LockoutsVotingZone 4Specific functions on each zone controller can be locked out by the local user. Thisinterface lockout prevents unauthorized inputs to the system, typically in publicareas or other areas where certain interface functions need to be prevented. Thelockout level is accessed via the Lockout parameter in the Installer ConfigurationMenu. Simply set the appropriate lockout level for each zone according to thesystem requirements. See Table 6 for details regarding the various lockout levels.Table 6: Lockout Level Function Details (Part 1 of 2)VotingZone 5Current Heat Demand 100% 0% 50% 50% 0%Heat Weight Set 100% 100% 100% 50% 100%Resulting Heat Weight to Rooftop Controller 100% 0% 50% 25% 0%Highest Resulting Heat Weight of Three Zones 100%Average of Three Highest Resulting Heat Weights 58.3%Average of Five Highest Resulting Heat Weights 35%Cool ActionVotingZone 1VotingZone 2VotingZone 3VotingZone 4VotingZone 5Current Cool Demand 0% 100% 0% 0% 100%Cool Weight Set 100% 50% 50% 50% 75%Resulting Cool Weight to Rooftop Controller 0% 50% 0% 0% 75%Highest Resulting Cool Weight of Three Zones 75%Average Cool Weight of Three Highest Zones 41.7%Average Cool Weight of Five Highest Zones 25FunctionAccess the local occupied setpoint using theUP/DOWN arrow keys.Press the local OVERRIDE key to command thelocal override function only. The local heatingand cooling demands are not sent to the rooftopcontroller, and the central system does notrestart. This function is required only whenperimeter reheat is used, and it is restartedduring an override period.Pressing the OVERRIDE key allows an overrideonly for the zone where the subject zonecontroller resides.LockoutLevel 0LockoutLevel 1LockoutLevel 2LockoutLevel 3Yes Yes Yes NoNo Yes No No24TEC Zoning Control System for Stand-Alone and BACnet® MS/TP Networked ApplicationsTechnical Bulletin