Output value does not equal to the position but proportional to it

[Roy19]

Hello everyone,

I have a servo-valve, servo-amplifier and LVDT closed loop system with 10V output and input modules. When I output a value (say 5 V), the actuator always go to the position of half of my output (for 5V is 2.5V). Has anyone encountered similar problems?

Any help would  be much appreciated!!!

Roy

[RIObotics · Accepted solution]

Hi Roy, sorry to hear you still have this problem.  Are there gain controls on your servo amplifier?  Sound like the gain needs to be doubled.

[Roy19]

Hi RIObotics,

Thanks again for your help!!!

This is actually another problem with a newly wired system. I finish my previous test with PID serveral months ago with another system and didnot have the chance to try your suggestion about the voltage drop in PID yet! 

Yes my amplifer has both gain and zero controls (called "feedback" in my amplifier, I suppose this is the same thing as you mentioned).The suggestion I got from others is to tune the gain as well. But I am still trying to figure out how the amplifier works and did not "dare" to change the default setting, because it is supposed to be well-tunned before shipped here.

Would you mind demonstrate a little bit more about how the amplifier works?

Best Regards,

Roy