Commissioning Instructions

Central Functions

Supply Chain Air 11

A6V12006922

Restricted

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For SAT Reset, there are two lower level functions that are used to control the setpoints. These are Supply

Changeover for Air (SplyChovrAir11) and Supply Temperature Setpoint (SplySpTSu11).

SplyChovrAir11 reads the Changeover conditions (Heating, Cooling, Neither, Neutral) from all the

terminals and determines what the Changeover mode should be for the AHU based on the terminals. For

this calculation, it is simply the larger number that will win. For example, if there are 20 terminals in

Cooling, while 10 are in Heating, the Changeover mode sent to the AHU will be Cooling.

This information is also sent to the next AF, where the actual Supply Air Temperature Setpoint is

determined. This is based on the Changeover mode, as well as demand signals read in from the terminals.

Each terminal sends a Heating and Cooling Demand signal (from 0-100%) to the Central Function. Then an

average demand is calculated from the highest 10 demands for both heating and cooling. This average is

used to determine how much to adjust the SAT between the max. and min. configured values. The final

calculated setpoint is then sent to the plant level where it is used to determine the temperature of the

outgoing air from the AHU.