Level Control Using USB 6008

[richie81]

Hi,

I'm looking for a bit of help with code for a Level Control project using a USB 6008. Basically my project consists of a reservoir and test tank. The test tank has a cistern arm turning a pot for my analog input. I have a 24vDc pump which is to be controlled by a Pulse Width Modulated Digital output. I'm not that familar with PID control or labview code for that matter, but ideally if I could achieve some form of PID that would be great!!

As of now, I have a program for my cistern arm, where I configured a DAQ assistant as an analog input. This VI basically simulates where the arm is at in the tank through a meter,tank,etc in the graphics. I also have a PWM program which I sourced off the net(this site I think) which has a DAQ assistant configured as a digital output. The PWM program has 'duty cycle' & 'milliseconds to wait' numeric controls on the front panel which can be adjusted manually during execution. I have managed to get both programs working with my hardware(digital output was tricky because of the current limitations of the 6008), but my main problem is trying to link these 2 programs... Maybe I'm going the wrong way about this though...

I understand also that there is a PID block in the labview code. It would be great to use this... I just find that any time I try to wire up say a DAQ assistant configured as an analog input to my Digital o/p DAQ assistant in PWM program, that trying every way possible I can't get it written without generating errors!! I would greatly appreciate if someone could help me or point me in the right direction with this. I have attached the analog input VI, and the PWM program. Thanks for your time,

Richie

MyProject2010.vi

NBMyProjectPWMProgram.vi