# Etrel Load Guard Configurator: reconstructing the meter's UDP protocol

> Etrel Load Guard Configurator is a Python CLI for discovering, reading and configuring Etrel Load Guard energy meters through a reconstructed UDP protocol. The author reports using REA with Ghidra on LoadGuardConfigurator.exe to recover packet fields and settings, then checking byte order and read-only measurements on a device. The tool includes dry-run writes and a simulator.

- Type: Case study
- Targets: Protocol
- Category: Community REA investigations
- Relationship: Author-reported mixed workflow
- Sources reviewed: 2026-11-07
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/XavierGeerinck/etrel-load-guard-configurator>
- Primary source: <https://github.com/XavierGeerinck/etrel-load-guard-configurator/blob/6e1fc40bf6a697c0a6a9fbae04f0806ba7acd2c0/README.md>
- Catalog page: <https://awesomerea.org/resources/etrel-load-guard-configurator-case/>
- Record JSON: <https://awesomerea.org/resources/etrel-load-guard-configurator-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/etrel-load-guard-configurator-case/index.md)

## Requirements & limits

- **Prerequisites:** Python 3.8 or later and network access to an Etrel Load Guard; discovery requires the same network segment.
- **Testing evidence:** The author checked read-only operations on a Load Guard with software version 10 and hardware version 257.
- **Limits:** Write commands pass tests and the simulator but have not been exercised on hardware.
- **License:** MIT license.

## Primary sources

1. <https://github.com/XavierGeerinck/etrel-load-guard-configurator/blob/6e1fc40bf6a697c0a6a9fbae04f0806ba7acd2c0/README.md>
2. <https://github.com/XavierGeerinck/etrel-load-guard-configurator/blob/6e1fc40bf6a697c0a6a9fbae04f0806ba7acd2c0/docs/PROTOCOL.md>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.