Can multimeter work in ACV mode under the control of LV?

[xy_4]

Hi,

I want to monitor an AC voltage signal by labview. First, I connect this signal with a multimeter in ACV mode, it works well. But whe I use LabView to take data from this multimeter, this meter automatically change to DCV mode. Is there some way to read ACV signal from this meter?

Thanks a lot

[AnalogKid2DigitalMan]

What make/model of meter?

What type of communications?

Can you attach your code?

I suspect that the vi contains a command to tell the meter to switch functions prior to taking a measurement.

[xy_4]

Meter: HP34401A

Interface: GPIB

Software: LabView 7.1

You are right. I also believe there is some code just change the mode of meter when the computer cintrol it. You know, I just use a data taking program which is coded by others. I am not sure which part of code you need. 😞

Thanks for reply

[AnalogKid2DigitalMan]

You can look at the block diagram and try to find a string (pink box) with the characters DCV in it. Try chaning it to ACV. This is just a guess, I do not know the command set for the meter. There may also be command controls on the front panel of the code.

[markus kossmann]

Check also, if you did enable the reset option when initializing the device.The 34401 defaults to DCV.after a reset.