S7 - restrict analog output voltage

[cjd1965]

Hi
I am getting a cpu 314c-2dp. I need to control hydraulic servo valves that need +/- 5V for proportional speed/direction.

I am looking into the best way to restrict the values, and typically use FC106 for analog outputs. I was considering simply setting FC106 to be -200% / +200% and resticting the input to +/- 100% but wondering if anyone has better ideas

Cheers

 

[metwally.mustafa]

you used the scalling and unscalling function to control the analoge signal

what about the feedback signal or actual speed of the proportional valve

(like linear pot)? i guss you used the FB41 PID function.......

 

[cjd1965]

Hi
Problem sorted... hacked FC106 into FC108 and halved the min/max values internally. Dont know why I didnt think of it before

Cheers