Do I need to subtract 1 from the register addresses listed in the Schrack documentation?

No. Schrack register addresses in hexadecimal map 1:1 to IO addresses. No minus one offset is required, unlike many other Modbus devices.

What baud rate and parity settings should I use?

The default settings are 9600 baud, 1 stop bit, and even parity. Make sure these match on both the meter and the Modbus gateway.

What data type are the registers on the Schrack MGX2040x?

All energy and power registers are encoded as float32 (two consecutive 16-bit registers). The template handles this automatically.

Can I use this template for other meters in the MGX2040x series?

Yes. The template is designed for the full MGX2040x range, including the MGX20400. The register layout is shared across this series.

Free Modbus template: Schrack MGX20400 Modbus power meter

This template reads energy and power data from the Schrack MGX2040x series Modbus power meter over Modbus RTU. It captures total energy, forward energy, reverse energy, and total active power. Register names are prefixed with GPWR, GE, and GI for straightforward energy monitor integration.

Name	Address	Function	Type	Unit	Access
Total Energy	24576	FC03	float32	kWh	R
GI Reverse Energy	24588	FC03	float32	kWh	R
GE Forward Energy	24600	FC03	float32	kWh	R
GPWR Total active power	20498	FC03	float32	kW	R

Schrack MGX20400 Modbus power meter

Overview

Key readings

Use cases

Installation

Things to watch for

Registers (4)

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