BAC_GenWthT_01
Functional description
The template BAC_GenWthT_01 reads the measured outside temperature via the global variable g_WthT_rPrVal.
The measured outside temperature is used to calculate an averaged or attenuated outside temperature. This is made available to other templates via the global variable g_WthTDamp_rPrVal.
The BACnet object WthTLmtCrit describes the global variable g_WthTLmtCrit. It describes an outside temperature value below which the frost protection mode should be activated in the systems.
The SpFrost AV object is used to describe the global variable g_H_SpFrost. This global value can be used to assign a setpoint for frost protection operation to one or more plants.
For the application of many other templates it is necessary to position this template once!
Interface
Block diagram
![BAC_GenWthT_01 2:](Images/jpg/12270241931__Web.jpg)
Program description
Instance | Type | Task |
---|---|---|
WthT | AV object for displaying the current outside temperature | |
WthTLmtCrit | AV object for entering and providing a global value for the critical outside temperature | |
SpFrost | AV object for input and provision of a global frost protection setpoint | |
DlyEn | TON | Delays reading of the first temperature value by 2 seconds after the start of the PLC |
Avrg | The function block Avrg measures the outside temperature every 15 minutes (900 seconds) and writes the value into a FIFO buffer (first in first out). The buffer has capacity for 96 elements. This results in a timeframe of 24 hours for averaging of the outside temperature. | |
WthTDamp | Output of the value of the averaged outside temperature |
Version history
Version number | Comments |
---|---|
1.0.1 | First release |