Opening multiple visa sessions

[voiceburg]

I'm having problems with opening multiple VISA sessions for communicating with 4 HP-34401A multimeters in LabVIEW 6.1. If you have a little bit of time, please take a look at what I have here to see if I'm doing something wrong.

Thanks

[Dennis_Knutson]

It would help if you included the VIs HP34401A Setup and HP34401A Read Meas No Wait. However, I did notice that do the setup for instruments at addresses 3 and 4 but not for the ones at 5 and 6. Also, in the first sequence, you're doing a VISA close for one instrument but the others are closed when the stop button is clicked. Also, if you could detail the actual problem you're having. Is an error code being generated? You could also simplify things quite a bit (i.e., not use sequences, the while loop termination) but that's a different subject.

[waldemar.hersacher]

I have made a look at your VI. I don't have the driver for the instrument I couldn't go into the subVIs and its documentation and I could not change it for you.

1. You initialise only 2 of the 4 meters. Initialize all meters.

2. In sequence 0 you close the session to the meter. In the next loop iteration it will not measure as you intended. Delete the "VISA Close" function.

3. The stop button would cause the while loop to exit. But your handling is a little bit complicated. Do following:
Delete the "not" and case where the stop terminal is connected. Wire the stop terminal directly to the termination terminal of the while loop. With the context menu set it to "stop if True". Wire the VISA sessions to the right border of the while loop and connect t
hem to the "VISA Close" function.

Waldemar