Drain pump on-off control

[gmarin4813]

I need to build a simple level controller in LabView by using a 0 to 5 V signal from the level sensor to control a drain-pump-relay that  stops the pump on low level, starts the pump on high level. Can some one give me a light on how to build this basic controler?

Thanks,

Gabriel4813

[parthabe]

Hi Gabriel,

Can U pl tell us more what re the exact "values" for Ur High & Low levels... ?!

Then only U can do a setpoint comparison to do the "Run" & "Drain" the pump ?

U can do even feedback of the result U get to run the pump continously to fill or drain the tank...

[gmarin4813]

The sytem is as follows:

An infrared, analogue level sensor monitors the level and generates a signal from 1 to 5 VDC. I am monitoring that signal through a small Data Aquisition System of LabView.
I want to use that signal to power the pump that drains the tank.
When the level is high (i.e. 5 V) turn on the pump
When the level is low (i.e. 1 V) turn off the oump.

What controler should I use and where do I find it in Labview. Also, how can I connect it to the DAS?

Thanks

[gmarin4813]

I'll appreciate some input as to how to create a .vi controller in Labview. I just need to control a relay to go on and off based on analogue input from 1 to 5 volts. Wher in Labview do I select the controler and how should I configure it.

I'll appreciate your input to help me solve this problem.

Thanks.

[xseadog]

Hi

what small data aquisition card are you using?

have you attempted to search the discussion formums for your solution?

have you checked out the labview examples provide with Labview?

if your sensor is providing a signal from  1 to 5volts then  I would  not use the full dynamic range to control it!

I would enable the act to commence from say 4.5 V  down to 1.5 volts. After sufficient testing then tweaking the system would be acceptable.

The more salient information you provide the  more satisfactory response you will recieve.

ie are you using Labview 7.1? what is your OS ?

regards
xseadog

[gmarin4813]

I am using LabVIEW 8. The DA is the NI-USB-6009. My OS is Windows XP
The sensor generates voltage from 0 to 5.3  and I am using the range from 1 to 4.5 v.
The question is how I create a controller in Labview to output digital signal on /off at 1 and 4.5 V respectively?
How can I configure such controller?
I have look in other threads but there is nothing similar.

Thanks.

[Dennis_Knutson]

There are numerous threads on using digital I/O and there are numerous shipping examples of digital I/O. All you need is a couple of comparison or In Range functions wired to a case statement. What you will need extra though, is probably some external circuitry to drive your relays. The 6009 has a low current output and is probably not enough to directly turn them on.