FC51 Danfoss VFD MODBUS

[damiens]

I need to control a FC51 Danfoss VFD with LS PLC. I need to start, stop & jog the drives.

I have set all the parameters as per manual for Modbus operation at 9600bps 8n1.


I am unable to start the drive I am sending the following frame to start the drive:


Address of Drive 2
Function 5
Coil 6
Data 1


Can someone help me, Danfoss service engineer has refused to help since I have not purchased the drive from their Official System House.

 

[gclshortt]

http://prom-electric.ru/media/fc51.pdf

Coil 07 is the start Bit

Hope this helps you out.
Regards,

 

[Michal_dk]

Hi Damiens!

I'm not in here as often as I would like, so I may be too late.

The Danfoss ModbusRTU requires Coils 2, 3, 4, 5, 6 and 10 to be high for the drive to run CW. Add Coil 15 to that mix and it will run CCW.

In the Danfoss world a stop command has higher priority than a start command (likely true in every reality), so you need to set all the Coils that in their "0" state have a stop meaning (2, 3, 4 and 5). Coil 10 "Data Valid" tells the drive if the data in the coils is to be acted upon, so this needs to be "1" for the drive to react on your command.

best regards

Michal_dk

 

[redbarron55]

I don't have the manuals handy, but often on drives you also have to have the hardware selected to enable the drive as well.