EMMTRY does not replace your lock. It replaces the button that opens it. Whatever currently triggers your electric strike, maglock, gate motor or garage opener, a wall switch, a keypad, a remote, does so by closing a circuit for a moment. A Shelly relay can close that same circuit on command, and EMMTRY decides when the command is allowed. This article explains that arrangement in enough detail to plan an installation.
A note before anything else: anything connected to mains voltage should be installed by a qualified electrician. Many gate motors and garage openers expose a low-voltage trigger input precisely so that accessories like this can be connected safely; use it.
What the controller does, and does not do
The relay's job is small on purpose:
- It receives an instruction from the platform: open now.
- It closes its output for a short pulse (for a strike) or holds it (for a maglock), exactly as the old button did.
- It reports its state, and optionally the state of a door or gate sensor wired to its inputs, back to the platform.
It does not hold the list of who may open the door. That list, the schedules, the roles and the log live in the platform, which is why the same relay serves a single door or a whole complex. Authorisation is checked at the moment of each request; the device never has to be reprogrammed when people change.
Choosing a model
Two Shelly devices cover most entrances. Both are bought from Shelly or any reseller; EMMTRY does not resell hardware.
Shelly Plus Uni is the usual pick for gates and garage doors. It runs on 8 to 24 V, has two dry-contact outputs (so open and close can be separate triggers) and two inputs for position sensors. It connects over WiFi and supports Bluetooth for setup.
Shelly Pro 2 is the pick for strikes, maglocks and anywhere a wired connection is preferred. Its two relays are potential-free, so they can switch the lock's own supply at whatever voltage it uses, and it mounts on a DIN rail with an Ethernet port for an always-on connection.
The platform also works with Shelly 1, 1PM, 2PM, 1 Mini, 1PM Mini, Pro 1, Pro 1PM and Pro 2PM, and with Shelly BLU door/window sensors for door-state reporting. The technical specifications keep the current list.
For sites without WiFi or wiring, the EMMTRY 5G controller connects over cellular (LTE-M or NB-IoT) and adds NFC and Bluetooth for on-site use. It is announced on the home page; leave your email there to hear when it ships.
Before you wire
Five questions that decide most installations:
- What does the lock expect? A strike usually wants a pulse of a second or two; a maglock wants power removed for as long as the door should be open; a gate motor wants a momentary contact on its trigger input. Check the lock or motor manual for the input it exposes.
- What voltage is on the circuit you are switching? This decides between the Plus Uni (low-voltage dry contacts) and a Pro model (potential-free relays for the lock's own supply).
- Where is power for the relay? The Plus Uni is powered from the same low-voltage supply many gate motors provide; a Pro model takes mains, which is an electrician's job.
- How does it reach the network? WiFi coverage at a street gate is often worse than at the house. A wired Pro model, or the 5G controller, avoids the question.
- Do you want to know the door's state? If so, plan a position sensor on the inputs. EMMTRY shows open and closed state in the app and can alert on a door left open.
Pairing and after
Once the relay is powered and on the network, it is paired to your property from the EMMTRY app. Pairing provisions the device with its own credentials to the platform; every connection between the device, the apps and the servers is encrypted with TLS. From then on the relay appears as an entrance you can grant, group and schedule like any other.
Two operational details that matter later:
- If a relay breaks, the device swap function moves every grant, group and schedule to its replacement in one step. Nobody has to be re-invited.
- If a relay goes offline, the activity log records it and the app shows the entrance as offline. The platform announces reconnection when it happens; it does not re-announce on every command.
A typical first installation takes under thirty minutes once the wiring question is settled. If your entrance does not fit the patterns above, send us the lock or motor model through the contact page and we will tell you what fits.