M580 PIDFF

[gcummings]

PIDFF Block FF Input, I am using FF with WW, My ff_int & otff_int = 0, my ff_sup & otff_sup = 40, I would expect when FF input = a number >= 40 the output should increase by that amount. That is not what I am seeing. Can anyone tell me what I am missing her? The loop is in Auto mode.

Anyone have any idea what I am missing here?

.outff = FF input

[john_m]

Hi

I don't know the solution for your pid but used a Feedforward is always complicated when  you have dispersion on your process. An open loop is not reassuring. The best alternative is to use Relaxc ( available under EAE and unity [trail version available on exchange))

See this video https://www.youtube.com/watch?v=wePez3n0h-E

Furthermore  Relaxc can replace predictive control, IMC, LQG, LQR, Kalman, ...  and of course the PID.

Stay tuned

[AlastairF]

Have you looked at the description of the PIDFF block in the Help file? See the Parametering section.

I think your problem is that you have ff_sup = ff_inf (you mention value of 40 for both).

If these are equal the FeedForward component is ignored ie not added to the output.

There is no need to go and buy a commercial add-on to get capable process control for most applications.