Shelly
Shelly PM Mini Gen3
- Wi-Fi
- Bluetooth
Verified September 2026
A tiny 16A power meter that hides behind a socket, in a ceiling rose, or spliced into a consumer unit to monitor a whole circuit, not just one device. Unlike a plug-in energy monitor, which only sees whatever is plugged into it, this wires inline on the live conductor, so it can sit on a cooker circuit, an immersion heater, or a lighting ring and total everything downstream. It is not a CT-clamp meter — no clip-on sensor, just two screw terminals — so the circuit needs isolating to fit it. No relay, just measurement, fully local on the core Shelly integration and cheap enough to scatter around the house.
In Home Assistant
| Control | Type | What it does |
|---|---|---|
| Power / Voltage / Current / Frequency | Sensor | Live circuit readings — measurement only, no switching |
| Total energy | Sensor (kWh) | Cumulative reading — refreshes roughly once daily, not live |
It's measurement-only — power, voltage, current and frequency update live, but the total-energy sensor only refreshes once daily around 3am regardless of what power is doing in real time, a confirmed open HA Core bug rather than a setup issue. Since it can't switch anything itself, the practical pattern is "measure here, act elsewhere": feed its live power sensor into an automation that trips a separate smart relay on a different circuit once draw crosses a threshold, rather than expecting the module to self-protect.
Specs
- accuracy
- Accuracy Class B per IEC 62053-21 (approx. ±1%)
- max load
- 16A single channel, 3840W max at 240V
- plug type
- n/a (in-wall wired module)
- dimensions
- 29 x 34 x 16mm, 13g
- installation
- Inline wired module (L/N screw terminals, no CT clamp) — behind a socket, switch, or in a ceiling rose/consumer unit; no relay switching
- standby power
- <1.2W
- energy monitoring
- true
- operating temperature
- -20°C to 40°C