keithley 2400 2182 driver labview help

[d.gelman]

Hey wha,

Thanks for the little direction,  I am doing something similar to your posted vi, but I am doing reversing given current, example -10uA and 10uA for x amount of times, rather than sweep.  More like a square wave.  Also I wish to perform in delta mode. Im fairly new to LabVIEW so following your vi and making sense of it will require some time.

Danny

[d.gelman]

Hey Albert,

I believe it is avaible for the 2400, because I am not getting any errors..  If you mind clearing it up for me

I would like to send -10uA and 10uA with a frequency and sample measurements using the 2182a with a much higher frequency --> many samples for each supplied current.

I dont believe I need to switch to visa routines because I am only using this bus, that work is tideous for my lack of experience.

I am having troubles understanding triggering and what exactly it does?

Also I would like to perform this in real time, source --> measure ; source --> measure and so forth... so I am confused why the 50000 RQS does as it is slowing down the tests significantly.

Thanks,

[Albert.Geven]

Why not measure with the 2400 also, voltage and current can be measured.

The other one is a bit better but your program structure hinders you yo change much.

That is why subvi's were invented. Hiding complexity and making stuff easier to program.

Also not using the errorIO wil generate errors when you don't expect them. That is a death sin for production measurements.

And you can mix visa and gpib (as long as your instrument uses gpib).

So why not check out the existing driver.

[d.gelman]

Hey Albert,

You've been a great help so far and I will definitely take a look into the errorIO when I get to my lab.  My set up is currently measuring voltage drop both from my 2400 and 2182a but I need nanovolt measurements as I am expecting extremely small voltage drops. 

What did you mean by:

"The other one is a bit better but your program structure hinders you yo change much.

That is why subvi's were invented. Hiding complexity and making stuff easier to program."

Attached (2182Delta_LV6) is an example vi that uses the 2400 and 2182 for ultra low measurements in delta mode.  This is the vi that I am using.  I also found an example of SCPI references on how to do the same procedure on page 107 of the user manual (attached). I put these SCPI codes into my first attempt and had a different result (not working sufficiently).  All these 3 were previously attached from an earlier post.  

My question is what are the differences? and what are the (dis)advantages of them? Do I need to worry about 2182 vs. 2182a?

Thanks again

[Albert.Geven]

What exactly goes wrong, speed or accuracy?

Normally an A behind the device does not change the software but often accuracy or speed.

I did not check in detail because there is alot that can go wrong and like to have more info before giving a meaning.

You should build small test programs to check what goes wrong and also for such exercises subvi's are great.

I keep telling use subvi's please why don't you do it.

With edit/create subvi it is so easy.