Analog output logic

[robertmee]

[Thread Hijack Response]

For the ORIGINAL POSTER, and the ORIGINAL PROBLEM... You aren't trying to write drirectly from the HMI to the Analog Module output word, are you? You seriously need to write to either an internal register in the PLC before the SCP.

It appears he's using a SCP (From Post #1):

I am using a scale w/parameters with the input source set as the HMI and the destination source set as the output addrsss.

It appears he's using the SCP in Ladder 2 with no conditional logic ahead of it, so I can only assume at this point that the HMI configuration is incorrect and no value is getting written to the input address of the SCP.

 

[Kev77]

Is anything moving between the screen and the PLC? Make sure your comm setup is good before anything else. Set up a toggle PB on the screen and tie it to a bit (example B3:0/1). Make sure the bit is not used anywhere in the program!. Try and toggle it and see if it changes in the program.