PZEM Monitor
PZEM Monitor turns your device into a real-time energy meter reader. Wire up one or more PZEM-004T v3.0 sensors — on a main panel, a solar inverter, an appliance, anywhere you want visibility into power draw — and PZEM Monitor polls them continuously, shows you what's happening right now, keeps a local history, and can hand everything off to Home Assistant without any extra configuration on the HA side.
Everything runs on-device. There's no cloud account, no external server, and no data leaves your network unless you explicitly turn on MQTT.
- Guided setup
A step-by-step wizard walks you through wiring: pick a serial port, connect one meter at a time, and the wizard finds it, assigns it a unique address, and confirms it's reachable before moving on to the next. Add as many meters as your bus can carry — the wizard tracks which addresses are already taken so you can't collide two meters by accident.
- Live dashboard
Every configured meter gets its own card: online/offline status at a glance, and — while online — instantaneous voltage, current, power, frequency, power factor, and accumulated energy in kWh. An alarm badge lights up if a meter reports a fault condition. The dashboard refreshes itself automatically; there's nothing to click to keep it current.
- Local history, no cloud required
Every reading can be logged straight to an on-device database on a schedule you control, with automatic cleanup after a retention period you set. Review it as a chart and a sortable table for any time range — last 24 hours, 7 days, 30 days, or everything — and export any range to CSV whenever you need the raw numbers elsewhere.
- Home Assistant, zero YAML
Flip on MQTT in Settings, point it at your broker, and every meter shows up in Home Assistant automatically via MQTT discovery — one device per meter, with voltage, current, power, frequency, power factor, and energy as proper sensors (energy correctly reported as an ever-increasing total, so HA's energy dashboard just works). No manual entity configuration, no YAML to write.
- Built for unattended operation
Missing or disconnected hardware never crashes the app — it keeps serving the dashboard and settings so you can fix the problem from your browser instead of needing a shell. Configuration is written safely to disk so a power loss mid-save can't corrupt your setup.
- REQUIREMENTS
One or more PZEM-004T v3.0 energy meters wired to a UART port on the device.
A Home Assistant instance and MQTT broker, only if you want the HA integration.
- PRIVACY
All readings and history stay on the device. Nothing is sent anywhere unless you turn on the MQTT integration yourself, and even then it only goes to the broker you configure.