DAQ Analog input

[james bond]

HI
i m using labview 7.1 & NI PCI 6251 M series DAQ card., SCB 68 connector box
I m trying to read voltage from the connector box & displaying it on a waveform graph
But even when there is no voltage being supplied to the connector box, i m able to c readings on my graph in labview.

& the amplitude is around 10.
wat cud be the problem.?

[devchander]

Well, there is absolutely no problem

Open channels can saturete/ dirft to +/- max values of the DAQ card

But, when you connect a voltage source, you do read the correct voltage, right??