SCP for analog out to VFD, want to be sure i have it right

so i want to use an analog output card, 1762OF4, and send a 4-20ma signal to a vfd for speed control, ill set the 4-20ma scale in the vfd from 4ma=0hz and 20ma=100hz. my plan is to set the SCP input min at 0 and input max at 1000. then the scaled min at 6240 and scaled max at 31200. Then the input value i was going to store in an N7 data file with an implied decimal, so example if wanted 72.4HZ i would have 724 in said N7 data file. does this sound adequate? have i missed anything?

I don't know the figures off the top of my head for what corresponds to 4mA and 20mA on that particular analog output card, but assuming 6240=4mA and 31200=20mA, then yes, what you describe is correct.

ASF said:

I don't know the figures off the top of my head for what corresponds to 4mA and 20mA on that particular analog output card, but assuming 6240=4mA and 31200=20mA, then yes, what you describe is correct.

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those are the figures according to the AB KBase technote. is there any way to tell someone else looking at the program down the road one day that the decimal is implied within the SCP instruction and N7 data files specific to it? or is the only way to do such a thing a Rung Description?

JZerb said:

is there any way to tell someone else looking at the program down the road one day that the decimal is implied within the SCP instruction and N7 data files specific to it? or is the only way to do such a thing a Rung Description?

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Add a rung comment, otherwise you could use a float instead of an integer and actually have the decimal point

Rung comments are pretty much it. I mean, if I looked at your program and saw 0-1000 being scaled to a drive output, and an input figure of 742, I'd probably assume what was going on correctly. But yes, just make the comment of that N7 register something like:

Motor ABC
Speed Reference
(% * 10)