All AI channels have the same value

[张蓓蕾]

I use the example aiex2.cpp for a multichannel AI read with the mseries devices NI6280.

This example works for one channel, but the other channels have the same value

For example: I set 5Volt on the first channel and then the other channel have 5Volt too.

What should I consider in the configuration?

[Steven_T · Accepted solution]

Hello Beilei,

I think that you are running into the AI ghosting issue.  Are the other channels you are using connected to ground when you connect the first channel to 5V?  If the other channels are floating, they will read the same value as the first channel...5V.

Steven T.

[i_lijun_2016]

Hello Steven T，

I also have the same issue but a little bit different.

device:NI6210.

Measure a voltage of a few millivolts by the differential mode.

All AI channels have the same value，all of them are error value（use a multimeter to measure the voltage between ai+ and ai-）.

This happens sometmes,at some point it will be normal again.