Common Communication Fault - INVT Goodrive3000 GD3000-01-055G-12 Operation Manual

Goodrive3000 series medium voltage inverters MODBUS protocol
If the operation is successful, the response may be as below (the same with the command sent by the
master):
Example 2: Set the Max. output frequency of the inverter with the address of 03H as 100Hz.
See the figures behind the radix point, the fieldbus ratio value of the Max. output frequency (P00.03) is
100. 100Hz timed by 100 is 10000 and the corresponding hex is 2710H.
The command sent by the master:
If the operation is success, the response may be as below (the same with the command sent by the
master):
Note: The blank in the above command is for illustration and it cannot be added in the actual application.
8.4.7.3 Example of MODBUS communication commissioning
The master is PC which applies the RS232-RS485 converter to transform signals. The PC serial port for
the converter is COM1 (RS232 interface). The commissioning software of the upper computer is the
commissioning assistant of the serial port and it can be downloaded on the internet. Try downloading the
software with CRC checkout function.
The commissioning command is to make the inverter with address 03H run forward (8.4.7.2 example 1):
Note:
Set the inverter address (P14.00) to 03;
Set the running command channel (P00.01) to communication running command channel as well as
select MODBUS communication channel for P00.02.
Click send; if both the route and setting are correct, the response message from the inverter will be
received.

8.5 Common communication fault

Common communication faults: no response to the communication or the inverter returns abnormal fault.
The possible reasons for no response to the communication:
Select wrong serial port: for example, if the converter is COM1, select COM2 during the communication;
The baud rate, digital bit, end bit and check bit are not the same with the inverter;
+ and - of RS485 are connected in reverse;
The 485 wire cap on the terminal board of the inverter is not plugged in. The wire cap is behind the
terminal block.
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