Greetings,
I have an F2424 that I'm setting up to control 5 VFDs via rs485. There are 3 Powerflex 400 drives and 2 Powerflex 4 drives. I can read the drives status easily using READMODBUS. However, when I use WRITEMODBUS or WRITEMB2, STATUS(2) returns 0. This is only the case with the PF400, the PF4 works fine.
I set up a serial monitor, to read what the plc was sending, then using the terminal, sent the commands manually to see what the response from the drive was, as follows:
PLC command: WRITEMODBUS 13, 102, 8192, 13586
"start command" 66 10 20 00 00 01 02 35 12 9E FD
response from PF400: 66 90 01 3C 1F
Function Code 16 sent Exception Code 1 returned
So I created the same command and sent manually from my pc only using Function Code 06 and repeated the experiment:
"start command" 66 06 20 00 35 12 1d 40
response from PF400: 66 06 20 00 35 12 1d 40
In the end I was able to manually start and stop the PF400
using Function Code 06, but always got Exception Code 1 when using Function Code 16. So my inital conclusion is that the PF400 drives only accept write function 06.
Question:
Will TBasic WRITEMODBUS and WRITEMB2 only use Function code 16? Is there an easy way to send Function Code 06 instead of 16?
Regards,
Derek