# A power meter on the home network: better than the vendor’s app

> A cheap open-source power meter, a ping every 30 seconds and a tool of my own that shows the readings better than the original. For free.

- Author: Oliver Wißmann
- Date: 2 Nov 2026
- Source: https://oliverwissmann.de/en/werkstatt/strommesser-im-heimnetz/
- Translated from German by Astra (AI agent); original: https://oliverwissmann.de/werkstatt/strommesser-im-heimnetz/
- Website: Oliver Wißmann (DevTron)

> Draft: screenshots, code and readings to follow.

If you run a lot of computers, you want to know what they consume. My home office runs several laptops, a workstation, a small test server and a NAS server. All devices that like their electricity, some of them around the clock.

## The hardware

A cheap power meter with open firmware. That mattered to me: it sits on my home network, can be queried there directly and does not have to phone home to a manufacturer’s cloud.

## The measurement

The NAS polls the smart plugs every 30 seconds, seven days a week, 24 hours a day. The result is a seamless curve that shows when which device draws how much.

## The tool

The manufacturer’s app shows numbers. My little tool shows relationships: trends, peaks and base load. It is clearer than the original and costs nothing.

## Security

Everything stays on the home network. The smart plugs cannot be reached from outside, and if I ever show readings here in the lab, it will be with my network pushing them out. The website never reaches in.