UniFi Relay

The Ubiquiti USL-Relay is a compact SuperLink relay module that bridges the gap between UniFi Protect and the equipment you already own. With two dry-contact inputs and two dry-contact outputs in a housing barely larger than a matchbox, the UniFi Relay lets you pull third-party sensors into UniFi Protect as triggers — and push UniFi Protect events out to sirens, strobes, gates, roller doors, lighting circuits and building systems that have no native UniFi support.

Because it communicates over SuperLink, Ubiquiti's long-range sub-GHz wireless protocol, the USL-Relay can be installed up to 2 km (1.2 mi) from a SuperLink Gateway with no cabling back to the rack. That makes it a practical answer for outbuildings, plant rooms, gatehouses, car park barriers and remote sheds where running structured cabling is expensive or simply not possible.

Everything is configured, monitored and automated in the UniFi Protect web application or the UniFi Protect mobile app for iOS and Android — no separate controller, subscription or licence.

Key features

• Two dry-contact inputs (I1/I2) — bring legacy PIRs, reed switches, panic buttons, water-leak probes, tamper loops, fire panel outputs or any open/short contact into UniFi Protect as an event trigger.
• Two dry-contact outputs (O1/COM/O2) — switch external devices from a UniFi Protect automation. Rated 10 A per port at 12–48 V DC or 12–240 V AC (12 A total UL / 16 A total IEC).
• SuperLink wireless, up to 2 km range — long-range 14 dBm sub-GHz link removes the need to cable the relay back to a switch or controller.
• Flexible DC power input — accepts 12 V, 24 V or 48 V DC via the VDD/GND terminal block, so it can share existing alarm, access-control or PSU circuits.
• Three mounting options — adhesive pad, wall screw fixing, or DIN rail for clean installation inside a distribution board or control panel.
• Built-in electrical protection — integrated 5 V TVS protection on the signal inputs and over-temperature protection that trips at 85 °C (185 °F).
• At-a-glance status LEDs — an RGBW status LED for the SuperLink connection plus dedicated white LEDs for signal input and relay output state, so you can commission and fault-find without opening a laptop.
• On-board test button — fire the relay manually during install and handover, with a separate recessed factory-reset button.
• NDAA compliant — certified CE, FCC and IC, and suitable for government, education and federally funded projects.
• Native UniFi Protect integration — appears alongside your cameras, sensors and door readers, with no additional software or recurring fee.

What you can build with it

Turn any existing sensor into a UniFi Protect trigger. Wire a legacy motion detector, magnetic door contact, gas detector or float switch into I1 or I2, and UniFi Protect can start recording, send a push notification, or arm a scene the moment the contact changes state.

Sound alarms UniFi can't reach directly. Wire an existing bell box, industrial sounder or strobe to an output, and let a UniFi Protect detection event fire it.

Automate gates, barriers and roller doors. A momentary dry-contact pulse is the standard trigger input on the vast majority of gate motors and barrier controllers, so the USL-Relay drops straight into that workflow.

Control lighting and general circuits. Switch a contactor or lighting relay when Protect detects motion after hours — useful for car parks, loading docks and site perimeters.

Integrate with third-party BMS, alarm and fire panels. Dry contacts remain the universal language between security systems, so the USL-Relay gives UniFi Protect a two-way handshake with almost any panel already on site.

Extend security to unwired buildings. With a 2 km SuperLink range, workshops, storage sheds, pump stations and gatehouses can be monitored and actuated without trenching fibre or copper.

How it works

1. Pair it. The USL-Relay connects wirelessly to a UniFi SuperLink Gateway, which must already be adopted in UniFi Protect. (The SuperLink Gateway is sold separately and is required — the relay will not operate standalone.)
2. Power it. Feed 12–48 V DC into the VDD/GND terminal block. The USL-Relay has no battery and is not PoE powered, so plan a local DC supply.
3. Wire your I/O. Land your sensor contacts on I1/I2 and your controlled device on O1/COM/O2. Note that the outputs are dry contact only — the relay acts as a switch and does not supply voltage to the load, so the load needs its own power source.
4. Automate it. Build rules in UniFi Protect: input state changes become triggers, and outputs become actions you can attach to camera detections, sensor events, schedules or manual control from the app.

Important before you buy

• A UniFi SuperLink Gateway is required and sold separately.
• Inputs and outputs are dry contact only. The USL-Relay switches circuits; it does not power them.
• Rated for indoor installation: 0–40 °C (32–104 °F) and 10–90% non-condensing humidity, with no published ingress rating. Use an appropriately rated enclosure for outdoor or wash-down locations.
• SuperLink operates on regional sub-GHz bands (US 915.6–927.6 MHz, EU 865.1–869.5 MHz). Order the SKU matched to your country's regulatory domain and pair it with a gateway in the same domain.
• Mains-voltage wiring must be carried out by a licensed electrician in accordance with local regulations.