Can I connect multiple ONOKOM TCL-3-MB-B gateways on one RS-485 bus?

Yes. Each gateway must have a unique Modbus slave address. You can change the address by writing to the service register at address 128. Ensure all gateways share the same baud rate of 9600.

Which registers are writable for controlling the AC unit?

Registers at addresses 2, 4, 6, 7, 8, 9, and 10 are both readable and writable. These cover on/off control, target temperature, fan speed, fan modes, and vane swing functions.

The gateway does not respond after wiring. What should I check?

Verify that the RS-485 A and B lines are not swapped. Confirm the baud rate is set to 9600 on both the ModbusCloud gateway and the ONOKOM device. Also check that the correct Modbus slave address is configured in the template.

Does one ONOKOM gateway support multiple TCL indoor units?

No. Each ONOKOM TCL-3-MB-B gateway connects to a single TCL indoor unit. For multi-unit installations, use one gateway per AC unit on a shared RS-485 bus with unique addresses.

Free Modbus template: ONOKOM AIR TCL-3-MB-B

Name: ONOKOM AIR TCL-3-MB-B
Brand: Onokom
SKU: 9df1e6ba-74d6-46ab-9907-860d77f58a1a

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Free Modbus template: ONOKOM AIR TCL-3-MB-B | ModbusCloud

Registers (16)

10 read / 13 write

Name	Address	Function	Type	Unit	Access
Indoor air temperature	3	FC03	uint16	°C	R
AC connected	20	FC01	uint16		R
Screen light (Status)	2	FC01	uint16		R/W
Sleep mode (Status)	8	FC01	uint16		R/W
Quiet mode (Status)	4	FC01	uint16		R/W
Turbo mode (Status)	7	FC01	uint16		R/W
Eco mode (Status)	6	FC01	uint16		R/W
Vertical vanes (Status)	10	FC03	uint16		R/W
Horizontal vanes	9	FC03	uint16		R/W
Indoor heat exchanger temperature	23	FC03	uint16	°C	R
Active (Control)	1	FC05	uint16		W
Loxone modes (Control)	15	FC06	uint16		W
Smart fan speed	8	FC06	uint16		W
Target temperature	5	FC06	int16	°C	W
Vanes swing	11	FC06	uint16		W
Modbus address (Service)	128	FC06	uint16		W

ONOKOM AIR TCL-3-MB-B

Overview

Key readings

Available commands

Use cases

Installation

Things to watch for

Registers (16)

Working with Modbus in your projects?

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