Current measurement capture

Hi everyone,
novice in Labview, currently using version 8.2.
attached is a simple vi program, purpose is to obtain data from a certain device, mainly using Agilent E3646A as DC Power Supply. I have a couple of questions...
1) how do i determine the byte count (Visa Read)? I wired Return Count (Visa Write) to byte count (Visa Read), the current seems constant
2) how do i implement by setting a voltage & current limit to the existing program?
3) how do i obtain the device's current consumption?
thank you so much!
Attachments:
Untitled 2.vi ‏24 KB

You DO NOT wire the return count output to VISA Read. The return count is the number of bytes written and has nothing to do with how many bytes you should read. You can look in the programming manual to get an idea of how many bytes the query will return. You can, however, put some large number for the number of bytes to read. The instrument will assert EOI at the end of the data so the VISA Read will automatically terminate when the EOI is detected.
The simplest thing to do is to use the existing driver for the E3646A. Is there a reason you don't want to? You can use the Tools>Instrumentation menu option to search for it or to go to the Instrument Driver Network.

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This solution is shown in picture TS_1.png
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I suggest you to write an e-mail to [email protected] . If you can, please send the sequence, and I could have a look on it.
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Attachments:
ts_1.png ‏39 KB
ts_02.png ‏70 KB

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cont_current_meas.vi ‏58 KB

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Current measurement capture

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