Using pci 6224

[GNS]

Hi all,

I m using PCI 6224 in one of the solutions. When i connect a floating dc voltage signal to the AI, in differential mode, the voltage level rises. It shows a false voltage. When I measure the voltage by DMM without connecting the cable, the voltage is OK. Can u plz. predict what problem may be?

Regards

GNS

[Christian Mergl]

Hi gns,

With floating signal source i would recommend to use RSE (referenced single ended) configuration for your DAQ-card.

BR, Christian

[GNS]

thanks for the reply...

our signal is floating there and we can not connect the negatives of the signals together. can we measure the alll +'s and all -'s in NRSE mode separetely...???  and we defferentiate the value later......will it work..???

[Christian Mergl]

Hi gns,

I think the attached picture will help you!

BR, Christian

[GNS]

thanks for your kind support....

cud i have the same doc in english..?? plz...!

[GNS]

HI,

How can we turn the ground reference off in PCi 6224.....??

[Christian Mergl]

Sorry for this mistake, I don't have it in english!

The following KB will explain the measurement for floting sources also: http://digital.ni.com/public.nsf/websearch/1FFCBE3451ABEE09862562970059881D

What do you mean with "turn the ground reference off" ?

BR, Christian