Controls a Fuji frequency inverter via Modbus RTU.
Overview
This template connects to the Fuji Electric FRENIC-ACE frequency inverter via Modbus RTU. It reads working frequency and analog input values, and allows writing frequency reference and motor operation commands from the ModbusCloud dashboard.
Key readings
Frequency Reference
Working Frequency
Analog Input C1
Available commands
Frequency Reference
Motor 1 Operation
Use cases
Monitor the working frequency of a ventilation fan motor in real time on a cloud dashboard.
Write a new frequency reference remotely to adjust pump speed without visiting the site.
Create an alert when the working frequency deviates from the setpoint by more than 5 Hz.
Log analog input C1 values over time to track external sensor readings connected to the inverter.
Send motor start and stop commands from the ModbusCloud dashboard during commissioning or maintenance.
Supervise multiple FRENIC-ACE drives across different sites from a single ModbusCloud account.
Installation
1Connect the ModbusCloud gateway RS-485 terminals (A and B) to the RS-485 communication terminals on the FRENIC-ACE inverter.
2On the inverter keypad or parameter tool, set the Modbus slave address (e.g. station number parameter) to a unique value and confirm the baud rate is set to 19200.
3Enable Modbus RTU communication on the inverter by setting the appropriate communication function parameters as described in the FRENIC-ACE manual.
4In the ModbusCloud platform, add a new device and import the Fuji FRENIC-ACE template from the template library.
5Set the Modbus slave address in the ModbusCloud device configuration to match the address configured on the inverter.
6Verify communication by checking that the working frequency and analog input C1 values appear on the live dashboard.
Things to watch for
01
Why does the frequency reference read value differ from what I wrote?
The read and write registers for frequency reference use different addresses. Reading is performed at register 2053, while writing uses register 1797. Both must be mapped correctly in the template for consistent results.
02
The gateway cannot communicate with the inverter. What should I check?
Verify that the baud rate on the inverter is set to 19200 to match the template default. Also confirm the Modbus slave address matches between the inverter settings and the ModbusCloud device configuration. Check RS-485 wiring polarity (A to A, B to B).
03
Can I send run and stop commands to the motor from ModbusCloud?
Yes. The template includes a writable Motor 1 Operation register. Make sure the inverter is configured to accept run commands via Modbus rather than from the local keypad or terminal inputs.
04
Do I need a termination resistor on the RS-485 bus?
If the gateway and inverter are the only two devices on the bus or the cable run exceeds 20 meters, add a 120 ohm termination resistor at the far end of the bus to reduce signal reflections.
Registers (5)
3 read / 2 write
Name
Address
Function
Type
Unit
Access
M05 Frequency Reference
2053
FC03
uint16
Hz
R
M09 Working Frequency
2057
FC03
uint16
Hz
R
M50 INPUT VALUE C1 ANALOG
2098
FC03
uint16
R
S05 Frequency Reference
1797
FC06
uint16
Hz
W
S06 Motor 1 Operation
1798
FC06
uint16
W
Working with Modbus in your projects?
ModbusCloud is the hardware-plus-software platform that installers use to monitor, visualise and control Modbus devices from one portal. This template is one of hundreds you can use right away.
