Supply chain changeover function for 2-pipe (SplyCho2Pipe11)

Overview

The application function "Supply chain changeover function for 2-pipe 11" (SplyCho2Pipe11) evaluates the heating/cooling demand from the rooms and decides whether the 2-pipe changeover water system will be set to heating or to cooling.

Function

The decision whether the water system should be used for heating or cooling is based on heating/cooling demand (HCDmd). An evaluated changeover condition is distributed via SplyChw-Grouping to the room segment to activate the heating or cooling sequence.

Cho2PipeModCmd - Cho2PipeModCmd is the mode command for the 2-Pipe changeover condition (Neither / Heating / Cooling). Cho2PipeModCmd can be overridden via BACnet with a higher priority.

Changeover determination logic - The segments with a heating or cooling demand are counted via the SplyChw-Grouping tag, HCDmd. The larger number of heating or cooling segments will win.

Example:
50 segments require cooling; 30 segments require heating

The evaluation = Cooling. The result will be distributed by the SplyChw-Grouping tag, ChovrCnd2Pipe to activate or deactivate the room controllers.

During heating, the cooling controllers are deactivated; during cooling, the reverse is true.

Configuration

None.

Note: Configuration in other AFs
The heating limit HLm in SplyHw11 and the cooling limit CLm in SplyChw11 must not overlap for a 2-pipe or 4-pipe system, otherwise the device-mode is set to "Off" outside midseason.

This means: HLm must be equal or less than CLm.