PXI-6704 bad current output

[ebalci]

Hi,

We have a PXI-6704 board. Using the DAQmx library in CVI I can -successfully- output currents like 5 mA, 10 mA and 12 mA through a 1K resistive load.

However when the demand exceeds 12.5 mA the output is stuck at 12.5 mA. I cannot generate currents between 12.5 and 20 mA.

No errors are returned by the DAQmx function calls.

I also tried MAX to control the current output manually but I got the same result.

Is this a calibration issue? Any comments?

Message Edited by ebalci on 07-17-2007 02:54 PM

[ebalci]

I solved the problem: 1K load is to much.

When the current output is left unloaded, the voltage value rises to almost 20V when you set the current to some nonzero value.
So I thought for current outputs the voltage drive can up to 20V.
But that is not the case under load.

When I replaced the 1K with a 200 ohm load I achieved the 20mA limit.