Every cell, not just one number
Watch all cell voltages side by side and spot the one that drifts before it limits your whole bank.
MoniWatt for Pytes plugs into the console port of your E-Box or V5 and turns the numbers hidden inside the BMS into a live dashboard on its own screen, on your phone and in Home Assistant.

A Pytes battery knows a lot about itself. Its BMS measures each cell, every temperature sensor, the current going in and out, how many cycles it has done and how healthy it still is. Most of that never reaches you: the inverter app shows a single percentage, and the rest stays behind the console port on the front panel.
MoniWatt for Pytes reads that port for you. You get the full picture of your E-Box 48100R or V5 on a 1.8-inch screen next to the battery, on a web dashboard you open from any browser at home, and as sensors in Home Assistant. No app to install, no cloud account required, and the box only reads: it never changes a setting in your battery.
Watch all cell voltages side by side and spot the one that drifts before it limits your whole bank.
State of health, cycle count and remaining capacity, read straight from the Pytes BMS rather than estimated by the inverter.
Cell and board temperatures, protection flags and warnings, with an e-mail when something needs a look.
Charge level, power and status on the box itself, readable at a glance when you walk into the garage.
MQTT discovery creates the sensors for you. A local JSON API is there for Node-RED, Jeedom or your own scripts.
Everything runs on your Wi-Fi. Remote access and the history dashboard are optional, never required.
The dashboard keeps the curve of the day: how fast the battery filled while the sun was up, how much the house pulled in the evening, and where the charge stood when the night started. You see at once whether your E-Box reached 100% or stopped short, and whether the evening load is eating more than you thought.
With the optional cloud history you can scroll back weeks and months, compare winter and summer, and export everything to CSV.
The box answers GET /api.json on your network and publishes the same values over MQTT. Home Assistant, Jeedom, Node-RED or your own script read them directly, with no cloud round-trip.
GET http://moniwatt.local/api.json?key=YOUR_KEY
{
"soc": 87, "voltage": 51.92, "current": -12.3, "power": -639,
"temperature": 21.5, "soh": 99, "cycles": 214,
"cells": [3.301, 3.298, 3.305, 3.291, ...],
"status": "Discharging"
}
| Models | E-Box 48100R, V5 series |
|---|---|
| Connection | console port, RJ45 cable included |
| Your existing wiring | Untouched: the box reads, it never writes |
| Network | Your home Wi-Fi (2.4 GHz); works without internet |
| Integrations | Home Assistant (MQTT auto-discovery), JSON API, Jeedom, Node-RED, Domoticz, openHAB |
| Cloud | Free and optional: live dashboard, 3 years of history, CSV |
| Power | USB-C, under 0.5 W |
Another Pytes model? Tell us when you order: your box is prepared and tested for it.

The box has one RJ45 socket for the battery and one USB-C socket for power. The supplied cable goes from the console port of your Pytes battery to the box; any USB phone charger powers it. It measures and sits on a shelf or screws to the wall next to the rack.
Pytes designed its batteries to talk the same console language as the most common 48 V rack batteries in Europe, which is why this box exists: the hardware is the one we already build and ship for Pylontech owners, with firmware tuned to the Pytes BMS.
Each box is prepared and tested in France before it ships, by the team that makes Pylon-Monitor for Pylontech owners.
Questions before buying? Write to [email protected]: a person answers.
€49.00
Pre-order price until 9 November 2026 · €59 afterwards
VAT not applicable (art. 293 B CGI) · shipping calculated at checkout
Ships on 10 November 2026 · free cancellation until dispatch
Order today. We test the box on Pytes hardware before it leaves the workshop.