Voltage or power readings appear as very large or very small incorrect numbers. What is wrong?

The register byte order for 32-bit floating point values changed in Etrel firmware v1.0.2. Ensure your wallbox firmware version and your ModbusCloud template version match. A byte order mismatch causes garbled float values.

Can I adjust the charging current remotely?

Yes. The target current and EV max phase current registers are writable. You can set these values from ModbusCloud to control the charging rate dynamically.

Which Etrel models are supported by this template?

The template is compatible with the Etrel Inch Home and Etrel Inch Pro. Both models use the same Modbus TCP register map.

The gateway cannot connect to the wallbox over Modbus TCP. What should I check?

Verify that the wallbox and the ModbusCloud gateway are on the same network or VLAN. Confirm that Modbus TCP is enabled in the wallbox settings and that the correct IP address and port are configured in the template.

Free Modbus template: Etrel Wallbox

This template connects Etrel Inch Home and Inch Pro wallboxes to ModbusCloud via Modbus TCP. It reads charging status, per-phase voltage, current, active power, energy consumption, and session data. It also allows setting target current, phase configuration, charger time, and charger restart.

Name	Address	Function	Type	Unit	Access
Charging Status	0	FC04	int16		R
Measured vehicle number of phase	1	FC04	uint16		R/W
EV max phase current	2	FC04	float32	A	R/W
Target current	4	FC04	float32	A	R/W
Frequency	6	FC04	float32	Hz	R
L-N Voltage (L1)	8	FC04	float32	V	R/W
L-N Voltage (L2)	10	FC04	float32	V	R/W
L-N Voltage (L3)	12	FC04	float32	V	R
Current L1	14	FC04	float32	A	R
Current L2	16	FC04	float32	A	R
Current L3	18	FC04	float32	A	R
Active Power L1	20	FC04	float32	kW	R
Active Power L2	22	FC04	float32	kW	R
Active Power L3	24	FC04	float32	kW	R
Active Power Total	26	FC04	float32	kW	R
Power Factor	28	FC04	float32		R
Total imported active energy in running session	30	FC04	float32	kWh	R
Running Session Duration	32	FC04	int64	s	R
Running Session departure time	36	FC04	int64	s	R
Charger Set time Unix Time (seconds since 1970-01-01 00:00:00 UTC)	1000	FC16	uint64	s	W
Charger Restart Value ignored, triggered by write	1004	FC16	int16		W

Etrel Wallbox

Overview

Key readings

Available commands

Use cases

Installation

Things to watch for

Registers (21)

Working with Modbus in your projects?

Free: RS485 and Modbus RTU installation checklist (PDF)

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