DDC-Suite; How is it possible to start with another controller than the preheater in the controller sequence?
In the controller sequence "cooler - heat recovery - preheater", always the preheater gets the enable-flag to start controlling. But sometimes it makes sense to start for example with the heat recovery instead of the preheater.
Here is the way to go.
1. Connect a flag to the output "Contr" from the "Fan start" fbox. This output enables the controlling during the startsequence from the air handling unit.
2. Between the fbox "Fan Start" and the first controller fbox, you have to program a chain with a "Dyn" fbox, one "set" and some "reset" coils. The "set" is to enable the heat recovery, the two "reset" are to reset the flags for the preheater and the cooler.
You can find these coils in the library "Binary / Ladder diagram". To do some tests, you can also introduce a "man" fbox.
3. In this example, we enable now to start the sequence the "heat recovery" fbox. That means, the first enable flag is going to the heat recovery controller. After this first initialisation, the enable flag is moving from one to the other controller as usual.
PG5 2.0 / DDC Suite
Last update: 23.05.2015 17:08
First release: 07.08.2012 06:15