7.9 Connecting the adjustable additional heat source
The adjustable additional heat source (K27) can be turned on and off with a potential-free relay, and it can be adjusted with 0–10 V regulation messages. Connect the additional heat source to the expansion module TC1.4 as follows:
On and off: relay Q2, contacts Q23 and Q24
Regulation message: Y2 and M, power supply G (24 V).
Figure 1. Connecting the adjustable additional heat source