Which baud rate and parity settings does this template expect?

The template is configured for 9600 baud with odd parity (1 stop bit). These are the factory defaults on WAGO 879 meters. If you have changed the meter settings, reconfigure them to match or adjust the gateway port settings accordingly.

Do I need to change the template when using a 879-3000 or 879-3040 instead of the 879-3020?

No. All three models (879-3000 4PU, 879-3020 4PS, 879-3040 2PU CT) share the same Modbus register map. The template works without modification for any of these variants.

Why are energy counter values not updating?

Energy counters start at register address 24588 and use float32 format. If values remain at zero, verify that current is flowing through the meter and that the CT orientation is correct on the 879-3040 model.

What byte order do the float32 registers use?

WAGO 879 meters use big-endian (AB CD) byte order for float32 registers. The template is preconfigured for this byte order. If you see unrealistic values, confirm that the byte order setting on the gateway matches.

Free Modbus template: WAGO 879-3020

Template for WAGO 879-3020 and compatible 3-phase electricity meters via Modbus RTU. It reads per-phase voltage, current, and power, as well as total active, reactive, and apparent power, frequency, and energy import/export counters. No writable registers are included.

Name	Address	Function	Type	Unit	Access
Voltage L1	20482	FC03	float32	V	R
Voltage L2	20484	FC03	float32	V	R
Voltage L3	20486	FC03	float32	V	R
Current L1	20492	FC03	float32	A	R
Current L2	20494	FC03	float32	A	R
Current L3	20496	FC03	float32	A	R
Power L1	20500	FC03	float32	kW	R
Power L2	20502	FC03	float32	kW	R
Power L3	20504	FC03	float32	kW	R
Frequency	20488	FC03	float32	Hz	R
Total active power	20498	FC03	float32	kW	R
Total apparent power	20514	FC03	float32	VA	R
Total reactive power	20506	FC03	float32	var	R
Total Energy Import	24588	FC03	float32	kWh	R
Total Energy Export	24600	FC03	float32	kWh	R
Total Energy Import L1	24594	FC03	float32	kWh	R
Total Energy Import L2	24596	FC03	float32	kWh	R
Total Energy Import L3	24598	FC03	float32	kWh	R

WAGO 879-3020

Overview

Key readings

Use cases

Installation

Things to watch for

Registers (18)

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