i have a real big Problem with custom scale and a usb 6000.
i have different pressure sensors. one is 0-10v direct Output, three i´m measuring about a 500Ohm resistor.
The power source is 24V. Plus are connected to 0,1,2 and i took gnd from power source to the measurement device.
In DAQmax i see the correct voltage on every channel. But i´m not able to make a scale. I tested every Version (linear, table etc). I´m getting error -200077
What can this be? How can i create my Scale?
Solved! Go to Solution.
Well, we don't know what you did (you failed to attach your VI). But have you tried doing this in MAX first? Open MAX, open Scales, and create your Scale (use the Help that MAX provides) -- be sure to Save (upper left corner of the right-hand Pane) the Custom Scale). Now plug in your Device, open it, and create a Task to acquire data from the Device. In the Voltage Input Setup, note the ability to use Custom Scaling -- choose the Custom Scale you just created. Note that the Max and Min of the Signal Input range will need to be in "Scaled" units, so if your device goes from -10 to +10 V, you have to be sure you specify Max and Min scaled values that don't exceed these voltages. Now save your Task.
You can now use this Task as a Task Constant for a DAQmx Start Task. This will cause DAQmx Read to scale the voltages it reads and output "scaled values" in units you defined. You can, alternatively, use the Create Scale function in DAQmx, but this is a little more complicated ...
Note that the Max and Min of the Signal Input range will need to be in "Scaled" units, so if your device goes from -10 to +10 V, you have to be sure you specify Max and Min scaled values that don't exceed these voltages.
This is the problem. You need to use the scaled values for the max and min inputs on the Create DAQmx Channel. So your max and min should really be 6 and 0 respectively.
Hmm -- between the time I wrote my previous response and the time it posted, you had posted your code. It looks a lot like the code I use, except (a) it is in German (which I don't think will cause any problems) and the Error Lines are missing! I'd add the Error Lines back in (my rule is "If an Error Line is Present, Wire It, with Few Exceptions"). If you get an error when you run the code, it could be a clue to the "bad" function ...
you have to be sure you specify Max and Min scaled values that don't exceed these voltages. This was the Problem.
Thanks all so much
One small question yet.
Has anyone an example of polynomic calculation?
X (factor) is clear. But how is about y?
In my example 0-6bar are 1,95V to 9,95V