1PM Gen4 Smart Relay

The Shelly 1PM Gen4 switches and meters one circuit, with Matter, Zigbee and Wi-Fi 6 built in. Automate the load and watch what it really costs.

$39.95 inc GST In stock · ships today
Generation
Module Size
Channels
Power Metering
Free shipping over $150 Order before 3pm Melbourne time on a weekday and it ships the same day.
30-day returns Unused items, easy online returns
3-year warranty Backed by Shelly

Everything you need to know

The Shelly 1PM Gen4 is a single-channel smart relay rated to 16 A, with power metering and Matter support. For a dry-contact output to run a garage door or gate, choose the Shelly 1 Gen4. It needs a neutral wire and a licensed electrician to install.

Product features

Smart control without swapping the switch

Keep the light switch or power point you already have. The 1PM Gen4 sits in the wall box behind it and adds app control, schedules and automations, while the switch on the wall carries on working.

  • Fits behind a light switch or power point
  • Works with toggle and momentary switches
  • Needs a neutral wire in the wall box

Measures power usage in real time

Built-in power metering shows live draw and energy history for whatever the Shelly 1PM Gen4 controls. Track what a heater or towel rail costs to run, spot a failed bulb when its usage drops, or get a notification when the washing machine finishes.

  • Live power draw and energy history
  • Automations triggered by power use
  • Switches heaters and pumps up to 16 A

Overpower and overheating protection

Set a maximum power limit and the relay switches the load off by itself when it's exceeded. It also has built-in overheating, overvoltage and overcurrent protection.

  • Configurable overpower cut-off
  • Overheating, overvoltage and overcurrent protection
  • Fans and LED drivers need an RC snubber

Works with Matter, or runs on Zigbee

Matter comes enabled on every Gen4 relay, so the 1PM Gen4 joins Apple Home, Google Home, Alexa or SmartThings directly. It can run over Zigbee instead for a Home Assistant setup, and it extends your Wi-Fi and Zigbee networks as a gateway for Shelly BLU sensors.

  • Matter enabled by default
  • Zigbee for Home Assistant setups
  • Wi-Fi 6 and Bluetooth 5.0

Off-peak schedules that run locally

Schedules and scripts run on the relay, not in the cloud, so they carry on through an internet outage. Run a pool pump or an irrigation pump in off-peak hours, switch office equipment off after closing, or cut a load when solar production drops.

  • Schedules and scripts run on the device
  • Built-in web interface, no cloud account needed
  • Keeps working when the internet doesn't

What is a Shelly relay?

Shelly Logo
Shelly Relays

A relay is a small module that hides in the wall box behind a switch, or on the rail in your switchboard, wired in between the power and whatever it controls. That might be a light, an exhaust fan, a towel rail, a pump, or the motor that opens your garage door. Nothing on show has to change. The switch stays on the wall and keeps working exactly as it does now, and the same circuit can also be turned on from your phone, on a schedule, or by an automation.

The channels
The number

One channel per circuit

The number in the name is how many things the module can switch on its own, from one up to four. A single light or exhaust fan takes a 1. A double light switch controlling two separate lights takes a 2, and each side still works on its own. The Pro 4PM goes up to four.

Din mounted
Pro and Mini

Where the module lives

Everything else in the name is about size and place. The standard module sits in the wall box behind your switch, and the Mini is a smaller version of it for when there is very little room left in the box. Pro units are built for the switchboard, clipping onto DIN rail, which is where whole circuits and three-phase work belong.

In wall Mounted
PM

What PM on the end means

PM is power measurement. Those models report what the circuit is drawing and the energy it has used over time, alongside the on or off state, so you can see what a heater or a pool pump actually costs to run. Models without PM switch the circuit and tell you nothing about it.

Local Control
Gen 3 and Gen 4

What the generation changes

The generation tells you which protocols the module speaks. Gen 3 is Wi-Fi and Bluetooth. Gen 4 adds Zigbee and has Matter built in, though it runs one or the other, not both at once. The wiring, the app and the local control are identical. Pro units carry no generation in their name.

The existing controls

Nothing you already use stops working

The switch on the wall keeps doing what it has always done, and so does the button inside the garage. Whatever controls that circuit now carries on working, and the relay adds a second way in from an app, a schedule or a voice assistant. Nobody in the house has to change how they do things.

Smart bulbs

Smart lights that stay reachable

Smart bulbs only work while they have power, so one flick of the wall switch makes them unreachable via an app, like Philips Hue. Set the relay to Detached and the bulbs stay powered while the switch becomes a button your smart home can read, which is how a system like Home Assistant gets the switch and the bulbs working together again.

Works with

Also works with
  • Pairs with Amazon Alexa
  • Pairs with Apple Home
  • Pairs with Google Home
  • Pairs with Home Assistant
  • Pairs with SmartThings
Matter Symbol

Works with Matter

Also works with Matter, so it can join other Matter platforms as well as the ones above.

Connects over
On your Wi-Fi

Joins your home network, so you control it from the app with no hub or bridge.

  • Wi-Fi
or
On your Zigbee network

Joins a Zigbee network you already run, like Home Assistant or SmartThings, instead of the Shelly app. Every one you add also strengthens that network.

  • Zigbee
Bluetooth

Used to set it up, and can also act as a gateway that connects Shelly's Bluetooth sensors, like the BLU Motion, to your network.

  • Bluetooth

Works offline

Keeps working on your home network when the internet is down.

Scripts

13

Give it jobs the app can't

Scripts add jobs the relay can't do with the Shelly app's schedules and actions alone, like acting on the weather forecast or sending an alert to your phone. Each one is a small program that runs on the relay itself: copy it, paste it into the device's script editor and press Start. It doesn't need a hub, a cloud account or a subscription.

Scripts are free; installing one takes about two minutes.

Which relay do I need?

Gen3 is the value pick for everyday Wi-Fi setups. Gen4 adds an upgraded processor, Wi-Fi 6 and Zigbee. Matter is on out of the box, so it pairs with Apple Home, Google Home or Alexa directly, without the need for the Shelly app. Pro is built to go inside your switchboard, clipping onto the same DIN rail as your circuit breakers, and connects over Ethernet as well as Wi-Fi.

If you want a reliable relay behind a switch at the lowest price, and you run the Shelly app or Home Assistant over Wi-Fi, Gen3 does the job. For a new setup, Gen4 is the one we'd pick. If you already run a Zigbee network, Gen4 slots straight into it, and because every Gen4 relay is also a Zigbee repeater, each one you add extends and strengthens that network. A relay on Zigbee gives up Matter and its own settings page, so you choose which each one runs. And if you're searching for Gen2, it shipped under different names, the Plus and Pro ranges.

The three lines
Feature Gen3 Gen4 This model Pro
Best for Everyday Wi-Fi setups on a budget Switchboards and bigger jobs
Connects over Wi-Fi Bluetooth Wi-Fi Bluetooth Ethernet
Matter On some models, turned on in settings Not supported
Mounting Behind the switch or power point DIN rail in the switchboard
Price from $22.95 $89.95
Everything in this family
Model Generation Module size Channels Energy monitoring Price
1 Gen3 Gen3 Standard 1 channel No $24.95
1 Mini Gen3 Gen3 Mini 1 channel No $22.95
1 Gen4 Gen4 Standard 1 channel No $34.95
1 Mini Gen4 Gen4 Mini 1 channel No $34.95
1PM Gen3 Gen3 Standard 1 channel Yes $25.95
1PM Mini Gen4 Gen4 Mini 1 channel Yes $39.95
2PM Gen3 Gen3 Standard 2 channels Yes $35.95
2PM Gen4 Gen4 Standard 2 channels Yes $49.95
Shelly generations: Gen 3 vs Gen 4 vs Pro

Specifications & Installation

Shelly 1PM Gen4 Smart Relay wired into a wall box behind a socket plate

Setup · 2:07

How to install it

Shelly's own step-by-step install, from isolating the power to wiring L, N, O and the switch input.

Watch setup video
Build
Type
Module
Module size
Standard Also available: Mini
Channels
1 channel Also available: Two channels
Form
In-wall
Housing material
Plastic
Power
Power
Hardwired
Supply voltage
110–240 V
Standby power
< 1 W
Model
Generation
Gen4 Also available: Gen3
Electrical
Max current per circuit
16 A
Neutral required
Yes
Neutral not needed
No
External protection
Cable protection switch in accordance with EN60898-1 (tripping characteristic B or C, max. 16 A rated current, min. 6 kA interrupting rating, energy limiting class 3)
Control
Dry-contact mode
No
Energy monitoring
Yes Also available: No
Drives blinds & shutters
No
Local control
Yes
Wi-Fi
Standard
802.11 b/g/n/ax
Range (indoors)
30 metres
RF band
2412 - 2472 МHz
Max. RF power
< 20 dBm
Bluetooth
Version
5.0
Range (indoors)
10 metres
RF band
2402 - 2480 MHz
Max. RF power
< 4 dBm
Zigbee
Extends the network
Yes
Range (indoors)
100 metres
Protocol
802.15.4
RF bands
2400 to 2483.5 MHz
Max. RF power
< 20 dBm
Environment
Operating temperature
-20–40 °C
Operating humidity
30–70 % RH
Max altitude
2000 metres
Physical
Size (HxWxD)
37x42x16 mm / 1.46x1.65x0.63 inch
Weight
27 g / 0.95 oz
Screw terminals max torque
0.4 Nm / 3.5 lbin
Conductor cross section
0.5 to 4 mm² / 20 to 11 AWG (solid, stranded, and bootlace ferrules)
Conductor stripped length
6 to 7 mm / 0.24 to 0.28 in
Mounting
Wall console
Shell color
Red
Terminals color
Grey (Mouse Grey)
Output circuits ratings
Max. switching voltage
* 240 V~
Max. switching current
* 16A (240 V~)
Sensors, meters
Voltmeter (AC)
Yes
Ammeter (AC)
Yes
Internal-temperature sensor
Yes
Microcontroller unit
CPU
ESP-Shelly-C68F
Flash
8MB
Firmware capabilities
Schedules
20
Webhooks (URL actions)
20 with 5 URLs per hook
Scripting
Yes
MQTT
Yes
Identifiers
SKU
SHE-RLY-0006
MPN
S4SW-001P16EU
Barcode
3800238071295

Wiring diagrams

Circuit overview
LN230 V~ 50 Hz1Light / appliance2Wall switchOSWLLLNNShelly 1PM Gen4
1Light / appliance2Wall switch
Active (supply)Neutral / 0 VSwitched loadSwitch signal / dry contact

In Australia, fixed 230 V wiring is licensed-electrician work. Use these diagrams to plan the job and brief your electrician.

Showing the whole circuit

Shelly 1PM Gen4

100%
LN230 V~ 50 Hz1Light / appliance2Wall switchOSWLLLNNShelly 1PM Gen4
1Light / appliance2Wall switch

Select a terminal to follow its wiring.

Common questions

Quick answers before you buy. We test this gear ourselves. Can't find yours? Ask our Melbourne team

Yes, though it's a small job. Shelly relays wire into 240V mains circuits, so in Australia a licensed electrician fits them, and a single relay doesn't take a sparky long.

Yes, this model needs a neutral at the install point. If your switch box has no neutral, look at the Shelly 1L or 2L instead: they're made for exactly that wiring.

Yes. Matter is enabled out of the box, so it joins Apple Home, Google Home, Alexa or SmartThings directly. It can also run as a Zigbee device on a hub such as Home Assistant instead.

Yes. This model meters its own output, so the app shows live power draw and consumption history. You can also set thresholds and have the relay switch off on them.

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