ONOKOM AIR GR-3-MB-B

Use cases

• Monitor indoor air temperature and heat exchanger temperature on a live dashboard for each Gree AC unit.
• Create alerts when an error code appears or the error count increases beyond a threshold.
• Remotely adjust target temperature and operating mode for Gree air conditioners across multiple sites.
• Schedule fan speed and vanes swing positions based on time-of-day rules for office buildings.
• Track AC connection status to detect offline units and trigger maintenance notifications.
• Log operating mode changes and temperature trends for energy reporting and optimization.

Installation

1. 1Wire the ONOKOM GR-3-MB-B gateway to the Gree indoor unit following the manufacturer's wiring diagram, then connect the RS-485 A and B lines to your ModbusCloud gateway (MCG or MLP series).
2. 2Set a unique Modbus slave address on the ONOKOM gateway by writing the desired value to register 128, ensuring no address conflicts on the RS-485 bus.
3. 3Configure the ModbusCloud gateway serial port for Modbus RTU at 9600 baud, 8 data bits, 1 stop bit, no parity (or match the ONOKOM gateway settings).
4. 4Import the ONOKOM AIR GR-3-MB-B template from the ModbusCloud template library and assign it to the correct Modbus slave address.
5. 5Verify communication by checking that indoor air temperature and AC connected status values appear correctly on the ModbusCloud dashboard.
6. 6For multi-unit setups, repeat the wiring and address assignment for each additional ONOKOM gateway on the same RS-485 bus.

Things to watch for

Registers (20)

15 read / 14 write

More Onokom templates

ON

ONOKOM AIR MD-VRF-MB-B

Onokom

Modbus RTU

Controls Midea air conditioners via the ONOKOM MD-VRF-MB-B gateway

0 registers2

ONOKOM AIR MD-3-MB-B

Onokom

Modbus RTU

Controls Midea air conditioners via the ONOKOM MD-3-MB-B Modbus gateway.

15 registers3

ONOKOM AIR MH-2-MB-B

Onokom

Modbus RTU

Controls Mitsubishi Heavy air conditioners via the ONOKOM MH-2-MB-B Modbus gateway.

11 registers2

ONOKOM AIR GR-1-MB-B

Onokom

Modbus RTU

Controls Gree air conditioners via the ONOKOM GR-1-MB-B Modbus gateway.

18 registers2

ONOKOM AIR HR-1-MB-B

Onokom

Modbus RTU

Controls Haier air conditioners via the ONOKOM HR-1-MB-B Modbus gateway.

17 registers2

ONOKOM AIR HS-3-MB-B

Onokom

Modbus RTU

Controls Hisense air conditioners via the ONOKOM HS-3-MB-B Modbus gateway.

20 registers11

More RTU templates

Alnor HRU

Alnor Systemy Wentylacji Sp. z o. o.

Modbus RTUCertified

Controls and monitors Alnor heat recovery ventilation units via Modbus RTU.

29 registers13

Heidelberg Wallbox Energy Control

AMPERFIED GmbH

Modbus RTUCertified

Controls and monitors Heidelberg Wallbox Energy Control EV charger via Modbus RTU.

22 registers67

connecdoor.controller

connecdoor

Modbus RTUCertified

Controls and monitors smart door access points via RS485

0 registers53

Wattsonic - Schmachtl Sun Energy Box

Wattsonic

Modbus RTUCertified

Monitors Schmachtl Wattsonic hybrid inverter via Modbus RTU

92 registers72

Alnor HRU-P

Alnor Systemy Wentylacji Sp. z o. o.

Modbus RTUCertified

Controls Alnor HRU-P heat recovery ventilation units via Modbus RTU.

49 registers7

E+E Elektronik EE600 - Differential Pressure Sensor

E+E Elektronik

Modbus RTU

Measures differential air pressure for HVAC and filter monitoring applications.

1 registers21