Need some confirmation…
I have a Fibaro FGS-222 that switches ON/OFF my central heating. The wire diagram - if only one relay is used - looks like this:
I have connected it like this:
where C.V. is the ON/OFF themostat input of my my central heating system. This allows the Fibaro to switch ON/OFF the heating and works fine. No connection is made between L and IN, so it operates potential free.
I would like to add the possibility to manually switch the relay, so use the S1in the first diagram. However, I see that it is connected to L (mains).
Is it correct that as long as no L is connected to the IN, I am still switching potential free?