Pro EM 50 Energy Meter

A two-channel energy meter for your switchboard, measuring power in both directions. Built for solar, with a relay for contactor control.

$149.95 inc GST In stock · ships today
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3-year warranty Backed by Shelly

Everything you need to know

A single-phase energy meter that lives in your switchboard on the DIN rail. It measures two circuits at once, reads power flowing both into the house and back out to the grid, and has a relay for switching a big load through a contactor. For metering on a circuit you're also switching, choose a 1PM or 2PM relay instead.

Product features

Two circuits, measured separately

The Pro EM-50 mounts inside your switchboard and measures two single-phase circuits through current transformer clamps, so you can watch the house on one channel and something specific on the other. It reports voltage, current, and both active and apparent power in real time, per channel.

  • Two measuring channels, one module
  • Live voltage, current and power on each
  • Measures through current transformer clamps

It sees the power going out, not just coming in

Most meters only count what the house draws. The Pro EM-50 measures the flow in both directions, so on a home with solar you can see what you're buying from the grid and what you're sending back to it as two separate numbers, rather than one net figure that hides both.

  • Measures what you use and what you export, separately
  • Suits homes with solar
  • Accuracy class B, within 1%

Your history stays on the device

It keeps up to 60 days of readings at one-minute intervals in its own memory. That means the detail is on the meter itself, not on a server somewhere, so it's still there if your internet drops out and it doesn't depend on a cloud account. An onboard clock keeps the timestamps right even when it can't reach a time server.

  • 60 days of one-minute readings stored on the meter
  • No internet or cloud account needed to keep them
  • Pull the data out as JSON or CSV

A relay for the contactor

It has a built-in dry-contact relay for driving a contactor, which is how you put a big load under control without running it through the meter itself. Hot water and pool pumps are the usual jobs.

  • Dry-contact relay for contactor control
  • Suits hot water and pool circuits
  • Switching stays separate from measuring

Wired into your network

An RJ45 port puts it on the network by cable, which is the most dependable option inside a metal switchboard. Wi-Fi is there as a fallback, and it talks MQTT, HTTP and WebSocket, all over TLS, so it fits into Home Assistant and anything else you run.

  • Ethernet, with Wi-Fi as backup
  • MQTT, HTTP and WebSocket, all over TLS
  • Works locally, with or without the cloud

What is a Shelly energy meter?

Shelly Logo
Split-core current clamps closed around the cables in a switchboard, beside a Shelly energy meter on the DIN rail

A Shelly energy meter measures the power a circuit is using. It shows how much that circuit is using right now, keeps a running total of how much it has used over time, and stores one-minute records on the meter itself. It does not turn anything on or off, so every switch and appliance on the circuit works exactly as it did before the meter went in. You see the numbers in the Shelly app, or in Home Assistant through its Shelly integration, with no Shelly account in the middle.

A Home Assistant dashboard showing the home's live power use in watts alongside its rooms, lights and devices
Power usage

See where the power goes

Clamp the mains where they land in the switchboard and you see what the whole house is using, right now and over time. Put a meter on a single circuit, like the hot water or the air conditioner, and you see what that one thing costs to run.

A towel hanging on a chrome heated towel rail in a bathroom
Automations

Switch a load off when it runs high

An automation can run when a circuit climbs past a figure you set, like turning a heater off during a high tariff window. The meter supplies the reading, and a relay or a contactor does the switching. The EM Gen3 and Pro EM-50 have a built-in output for driving a contactor.

Solar panels across the tiled roof of a house on a sunny day
Solar

Import and generation, separately

One channel on the mains and one on the solar circuit gives you what you imported and what your roof made, as two separate numbers. A single channel nets them together and hides both. The clamp reads the current in the cable, so the meter works the same whoever made the panels or the inverter.

A front-loading washing machine under the bench in a laundry, beside a bank of drawers
Alerts

Know when something finishes or fails

When a circuit drops to nothing, whatever was running has finished, so an automation can tell you the washing machine is done. An old fridge or a pool pump drawing more than it used to is often the first sign it needs a service.

Getting started
1
Start with what you want to know Start here

One appliance, or the whole house? A single circuit you can reach in the wall is an EM Mini Gen4 job. The EM Gen3 clamps up to two circuits, or the mains of a single phase house. For something more substantial that lives in your switchboard, look at the Pro range, which clips onto the DIN rail.

2
Add more as you go Then

Each meter works independently, so you can start with a single circuit and add more as you need them. They don't need to match: mix models and generations, and they sit side by side in the Shelly app or Home Assistant.

What's in the box

1× Shelly Pro EM-50 energy meter
DIN rail mount, two metering channels
2× 50 A current transformer clamp
One per channel

Works with

Also works with
  • Pairs with Amazon Alexa
  • Pairs with Google Home
  • Pairs with Home Assistant
  • Pairs with SmartThings
Connects over
On Wi-Fi or Ethernet

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

  • Ethernet
  • Wi-Fi
Set up over Bluetooth

Used once, to get it onto your Wi-Fi.

  • Bluetooth

Works offline

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

Scripts

15

Give it jobs the app can't

Scripts add jobs the meter 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 meter 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.

Specifications & Installation

Shelly Pro EM 50 Energy Meter and its retail box

Setup · 2:18

How to install it

Shelly's own step-by-step install, from isolating the power to mounting it on the DIN rail and wiring it in.

Watch setup video
Power
Power
Hardwired
Standby power
< 3 W
Metering
Phases
Single-phase
Channels
2 channels
Measured by
CT clamp
Max current per circuit
50 A
CT clamps included
Yes
Accuracy (±)
1 %
Data
On-device history
60 days
Electrical
Relay output
Yes
Power supply voltage AC
100 - 260 V, 50/60 Hz
Power supply voltage DC
N/A
Build
Form
DIN-rail
Housing material
Plastic
Wi-Fi
Standard
802.11 b/g/n
Range (indoors)
30 metres
Bluetooth
Version
4.2
Range (indoors)
10 metres
Environment
Operating temperature
-20–40 °C
Operating humidity
30–70 % RH
Max altitude
2000 metres
Physical
Size (HxWxD)
94x19x69 ±0.5 mm / 3.70x0.75x2.71 ±0.02 in
Weight
63 ±1 g / 2.22 ±0.05 oz
Mounting
DIN rail
Screw terminals max torque
0.4 Nm / 4.43 lbin
Conductor cross section
0.5 to 2.5 mm² / 20 to 14 AWG (solid, stranded and bootlace lugs)
Conductor stripped length
6 to 7 mm / 0.24 to 0.28 in
Color
White
Output circuits ratings
Max switching voltage AC
240 V
Max switching voltage DC
N/A
Max switching current
2 A
Sensors, meters
Internal-temperature sensor
Yes
Voltmeter (RMS)
100 - 260 V
Voltmeters accuracy
±1 %
Ammeters (RMS via CT)
0 - 50 A
Ammeters accuracy
±1 % (5 - 50 A), ±2 % (0 - 5 A)
Power and energy meters
* Active and apparent power * Active and apparent energy * Power factor
Measurement data storage
At least 60 days of 1 min data resolution
Data export
* CSV for PQ recorded values * JSON format export through RPC
Radio
RF band
2400 - 2495 MHz
Max. RF power
<20 dBm
MCU
CPU
ESP32-D0WDQ6
Flash
16 MB
Firmware capabilities
Webhooks (URL actions)
20 with 5 URLs per hook
Scripting
Yes
MQTT
Yes
CoAP
No
Identifiers
SKU
SHE-SNS-0003
MPN
SPEM-002CEBEU50
Barcode
3800235268148

Common questions

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

In the switchboard, on the DIN rail. It's licensed-electrician work in Australia.

Yes. It measures the flow in both directions, so you see what you're buying from the grid and what you're exporting as separate numbers rather than one net figure.

Only through a contactor. The built-in relay is a dry contact for driving one, not an output that carries the load itself.

No. It runs on your own network, stores its own history and speaks MQTT, HTTP and WebSocket locally.

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