Write a value via Modbus to servo drive

[Jamie123]

Hello,

I have almost successfully established Modbus communication with a servo drive. I say almost, I cant read the register but I cant write to them. I want to change the speed via a button on the HMI. I get a -11 on the stats tag which is timed out.

Could someone please have a look at the ladder for sending the modus write. Have I missed something?

 

[Joe Tauser]

Post a picture of your Modbus table

I would first try making a Modbus entry with periodic timed read to see if the communication parameters and wiring  was configured properly.  Then worry about trying to call it from the ladder diagram.

Joe T.

[Jamie123]

Thanks Joe,

I made a school boy error of which I am too embarrassed to mention.

[Ausman]

Aw shucks Jamie, come on.  Show us!  Show us! 

cheers,  Aus

[Jamie123]

Ok,

I forgot to select "read"

Dunce hat is on

[Flex727]

There are so many settings involved in network communications (with any PLC), that I don't think I've ever written a project from scratch where I didn't miss getting some setting right.