Fibaro Relay to Shelly 2.5 problem with contacts

Hello all,

Before I used a Fibaro FGS 222 Relay switch for my pool deck to switch it open or close (3 wires total) A is general, B is open, C is close.

To do this I used:

And then connected side wire A to IN on the Fibaro, wire B to Q1 (open) and wire C to Q2 (close).
With mains (230v) connected to N and L.

Now Im trying to do the same with the Shelly 2.5 however, when I connect mains (N and L) on the SHelly that works,

but then Im trying to do the same as the Fibaro (but im missing the IN like on the fibaro).

When I connect the 3 cables for example to:

  • wire A to O1, wire B to SW1 then the fuse powers off

Is there any way for me to get the same as with the Fibaro so it just works? Or do I need another Shelly device?

O1 is Output, SW1 is SWitch, so I’m not surprised that doesn’t work.

I don’t have experience with the Shelly 2.5, but looking at the manual, I think this is how you should connect it:

  • wire A sounds like the Live wire, so it needs to be connected to both L’s (use a Wago connector or a terminal block to “split” the wire)
  • wire B connects to O1
  • wire C connects to O2

And of course also connect the neutral wire properly.

Thanks, get that :slightly_smiling_face: @robertklep

However, if A connects to L, then where does the + and - of the main power go, to power the module?
Cause I had + to L and - to N now.

You need to specify the Voltage your pool deck is using. Is it 220V AC or some lowered DC?

The pool deck are 3 dry contacts that ‘switch’ on or off, so there is no voltage on those.
It’s just a simple 'if wire 1 and 2 are connected, pool deck is open, 'if wire 1 and 3 are connected, pool closes.

Ah, in that case the Shelly 2.5 isn’t the right device to use. You need potential-free switching, which the Shelly doesn’t do from what I know.

Or you can use Shelly 1 (not PM version) that has potential free relay. But only 1 circuit can be controlled.

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I would recommend hiring an electrician to do the connection.