Unable To Get Lab view vi to display current signal

Question

I am using a Vishay Linear Displacement Transducer to measure linear displacement, this is how my current connections are
( The Vishay LVDT allows full bridge connections)
1. I coonected the wires from the LVDT to SCXI 1321 terminal block. The terminal block is pluggeg to the scxi 1001 chassis, and i have a pci-6033E card installed on the system.
2.I downloaded the continous strain measurement vi from the example vis.
here the problem starts
1. The signal that is being displayed on the VI is a always a linearly increasing signal.
2.How ever there is a change in the siganl when ever i make a change on the LVDT, even then a continious varying signal.
3.The vi at any point is not displaying the current signa
l.
Is there something which i am missing i am new to Labview and all this connections. can anyone help me on this

Answer 1

I'm assuming that if you have the SCXI-1321 terminal block, that it's connected to an SCXI-1121 universal input card in the SCXI chassis.
First, by using the 1121, determine if any excitation is occurring. Connect a multimeter and measure the voltage across the channel 0 excitation + and -. Is there excitation?
The VI that you are using does not set up the excitation voltage; it assumes that you are supplying the excitation externally, with some other power supply. You can use the 1121 to excite the Vishay, you just have to program that in.
Next, make sure that you are calling the correct channel. On the front panel, where you see the "channels" string, do you have something like "sc1!mdx!0", where sc1 is the scxi chassis number, mdx is the module
number of the card (md1 for first slot, md2 for second slot, etc), and 0 is the channel on the card.
If you just put in 0, it's going to try to use the analog input channel of your PCI-6033, not the SCXI-1121 channel.
Hope that helps some.
Mark