Relays and in-wall modules

Sonoff SPM-4Relay stackable power meter module with 4 relays 20 A

Renting rooms or running a workshop means knowing where the kilowatt-hours go: SPM-4Relay meters four 20 A lines separately and works only paired with the SPM-Main head unit.

Sonoff POWR3 25 A / 5500 W Wi-Fi smart switch with energy monitoring

Built for the heaviest loads in a home — instant water heaters, electric boilers, saunas — the POWR3 switches up to 25 A / 5500 W and meters every kilowatt-hour they burn.

A 433 MHz key fob in your pocket opens the gate where Wi-Fi never reaches, while eWeLink keeps the schedules — the 4CH Pro R3 packs four 10 A relays into one DIN box.

One pair of wires is all a fan-with-light usually gets — iFan04-H sits in the fan canopy and splits the light and three fan speeds into separate smart commands.

A pump, a gate drive, yard lights and a workshop socket would normally take four relays — the 4CHR3 fits all four 10 A channels in one DIN-rail box, each on its own schedule.

A 2024-built flat has a two-gang switch but no blue wire in the box — the MINI-ZB2GS-L makes both lighting lines smart without a neutral, over Zigbee.

Thirty Wi-Fi clients on the family router are plenty — this Duo keeps both lighting lines off the 2.4 GHz band, runs them over Zigbee and relays the mesh as a router.

Sixteen-amp relays run out of margin next to a storage water heater; the POWR320D carries up to 20 A with room to spare and logs every kilowatt-hour of heating, hour by hour.

One Duo module behind a double rocker runs both lighting lines at once — chandelier and sconce keep their own wall keys yet switch independently via app or voice, 10 A per channel.

A glance at the relay tells you watts, volts, amps and total kWh on its built-in LCD — no phone required, with six months of hourly history kept in eWeLink.

POW Origin turns electricity-bill guesswork into hourly kilowatt-hour records — a week of eWeLink charts shows which appliance leads, with six months of history kept.

See what each of two loads really draws: the DUALR3 meters voltage, current, power and accumulated kWh independently per 10 A channel, with overload cut-off.

Matchbox-sized and 40% smaller than the ZBMINIL, the ZBMINIL2 tucks into the cramped box behind an existing switch and makes the light smart with no neutral.

A boiler or a gate motor does not want 220 V from a relay — it waits for two signal wires to close, and the MINI-D dry contact does exactly that on app, schedule or voice command.

A regular relay will not fit behind the switch in a shallow flush box — the 39.5×33×16.8 mm MINIR4M will, 40% smaller than MINIR2 and with a Detach Relay mode on top.

Roller blinds, curtains or an awning drive gain app and voice control through Motor mode, while Switch mode turns DUALR3 Lite back into two independent 10 A relay channels.

Hidden in the box behind a two-gang switch with no neutral, the Moes Zigbee module runs two light lines from the app while keeping the wall key.

Tucked behind an existing 2-gang switch, this Matter-over-Wi-Fi relay joins Apple Home, Google Home and Alexa directly, with no extra gateway to buy.

When a renovation already runs a neutral to every switch box, the ZBMINIR2 uses it to keep a light on local Zigbee — controlled by your hub, not a cloud.

Lighting a whole flat takes a relay per light point, so unit price decides: the Wi-Fi MINIR4 Extreme keeps 10 A and Detach Relay while costing less than its Matter sibling.

Countless DIY smart homes began with a cheap Sonoff Basic relay. The fifth generation keeps that recipe — one 10 A line, nothing extra — and now speaks Matter.

A watering valve on a schedule, a heater on a timer, garage lighting from your phone — the BASICR4 covers these first automation jobs with one 10 A channel at minimal cost.

Z-Wave Long Range DIN-rail relay with 3 potential- channels rated 16 A each (48 A total), Z-Wave 800 series, 110-240 V; a Z-Wave controller is required.

Z-Wave DIN-rail relay with 2 channels, 16 A per channel and 25 A total, plus built-in power metering on each circuit. A compatible Z-Wave gateway is required.