I recenty ran into a problem when measuring 6 equal voltage signals. When using a g

[pops]

ood quality digital meter all voltage signals where equal and also using the labview test panel all voltage signals where equal. When measured by my vi i found that the voltage signals where not the same 2 of the channels displayed almost twice the amount.After changing the channel order using the I/O tabs on the right of the control panel I found i got the correct voltage readings. What caused my vi to diplay incorrect voltage readings due to the order of my I/O channels?I am using Labview 6.0 with a SCB-68 shielded I/O Connector Block interfaced with a NI-DAQ Multifunction I/O board PCI-MIO-16E-4.

[Filipe A.]

ood quality digital meter all voltage signals where equal and also using the labview test panel all voltage signals where equal. When measured by my vi i found that the voltage signals where not the same 2 of the channels displayed almost twice the amount.Hello;

I couldn't open the attachment you posted. However, you probably set the wrong input limits for your gains or had a too small interchannel delay in between channels that wasn't letting the instrumentaion amplifier to settle down properly.

A good way to make sure your VI is the cause for the problem is to run one of the Labview shipping examples to do the acquisition. The best one to try is the one named Continuous Acquisition and Chart(buffered).vi.

Regards
Filipe A.
Applications Engineer
National Instruments