Opening the street door from your phone is one of the most appreciated automations and one of the worst explained. Most write-ups skip the two things that decide whether it works: which model is suitable and where exactly it connects.
First: not every Shelly will do
You need a model with a dry-contact output — one that closes a circuit without putting voltage into it. These work:
- Shelly 1 Mini Gen4 — the fullest: Wi-Fi, Bluetooth, Zigbee and Matter.
- Shelly 1 Mini Gen3 — Wi-Fi and Bluetooth, cheaper and ample for this.
- Shelly Wave 1 Mini — if you already run a Z-Wave network.
The “1PM Mini” models will not do, Gen3 or Gen4. They look alike in name and size, but their output delivers 230 V instead of a potential-free contact. Putting 230 V into a door-entry circuit running at 12 or 24 V destroys the control unit.
That is the expensive mistake here, and it comes from the difference between “1 Mini” and “1PM Mini” being two letters.
Second: find out which system you have
There are two families and only one takes this arrangement directly.
Analogue — most installations in Spain
Classic four-wire-plus-common wiring, with a physical button closing two terminals. This is the one that works.
To confirm it: multimeter in continuity mode across the door-release terminals. If pressing the handset button gives continuity, it is analogue and you are set.
Digital bus — Comelit Simplebus, Fermax Duo, 2Easy
Two wires carrying coded messages, not simple contact closures. A Shelly wired in directly does nothing here: there is no pair of terminals to close.
It can still be automated, but you need the manufacturer’s own relay module, with the Shelly driving that module. Check which family you have before buying anything.
Third, and this is the part nobody mentions: where to connect it
In parallel with the door-release terminals, not with the button’s.
They sound like the same thing and are not. The button can be subject to the control unit’s internal logic — only enabled while a call is in progress, for instance — whereas the door-release output always responds. That output is on the manufacturer’s wiring diagram.
Wiring in parallel also leaves the original cabling untouched: the handset keeps working exactly as before for anyone not using a phone.
Power: separate, always
The Shelly needs its own 110-240 V supply. It cannot run off the door-entry bus, which works at 12-24 V and has no current to spare for this.
That is usually the real constraint on the job: if mains does not reach the handset box, you either take it there or find another spot.
Two settings you must not skip
- Auto-off after 1 or 2 seconds. A door release is a coil meant for short pulses; leaving it energised heats it until it burns out.
- “Detached” relay mode, to decouple the physical input from the output so the button cannot interfere.
Safety
Cut the power before touching anything and confirm it is dead. If the handset box shares a cavity with 230 V circuits — common in older buildings — take extra care with insulation.
And a practical warning: in a block of flats, the entrance control unit is not yours. Talk to the building manager before working on it.
Same dry-contact principle as in automating a garage door. The app and the console work with Gen2, Gen3 and Gen4.
How to use both, section by section: mobile app manual and web console manual.