Get dry contact status

Hi community,

I will have in the future an intercom that can close a dry contact with a scenario.
Is it possible to get that info in Home Assistant, with a Shelly 1 for exemple?

Thank you very much, regards !

Sure just hook it up to the switch contacts in the Shelly (SW & L). You don’t have to connect a load. But you will need power for the Shelly 1 and you will need to set the power source jumper appropriately.

For extra low voltage:
Screenshot_2020-04-28 Shelly1_User_Guide_EN_v5 pdf

For low voltage:
Screenshot_2020-04-28 Shelly1_User_Guide_EN_v5 pdf(1)
Make sure your dry contacts are rated for the voltage if using it this way.

But in that case, won’t I send current on the dry contact (the L will be common with the power and the dry contact) ?

Yeah which is why I said:

A dry contact is jut a switch. A switch with a voltage and current rating. And not connected to anything else.

Unless you are really talking about an open collector output (completely different thing) which is a transistor that shorts to ground when on. Bad things would happen in this case.

What is your intercom make and model?

I’ll look up the manual and see if it can be done this way.

It will be a DS-KH6320-WTE1 from HIKVISION :

https://www.hikvision.com/en/products/Video-Intercom-Products/IP-Series/Value-Series/ds-kh6320-wte1/

It has 2 “relay output”.

Thank you very much for your help !

Yeah that is a terrible datasheet and manual. No ratings anywhere for the relay contacts.

I’d contact them and ask what the rating of the relay contacts are just to be safe, but as both the intercom and Shelly can work on 12VDC and as the Shelly will draw next to no current into it’s switch input, I’d put money on you being safe to use the first wiring diagram I posted, the one for for extra low voltage.

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Exact same problem here…
(Also DS-KH6320-WTE1 and trying to catch the button press “event” with help of the relay output).
Have you tried to use the Shelly for the relay? Thanks!

I haven’t installed it yet…
No answer from the support either…

Maybe you can give it a try and tell us ^^ ?