Can i use arduino instead of ni usb 6009 to make a power quality analyser. i have seen a project where someone used ni usb 6009 and lab view for data acquisition. My question here is, can i replace ni usb 6009 with an arduino?
They're for different purposes - the NI USB is designed for data aquisition and interfacing between analog and digital electronics and a desktop computer.
You could definitely set up an arduino to pass data back over UART serial, or over a network. It would certainly be cheaper (hell, you can get arduino clones for the cost of all those screw terminals on the NI USB alone!) - but it would also not be as good at this task.
The NI USB has higher resolution ADC's, and a quick read of the datasheet suggests that it has a sample rate that the arduino isn't going to reach. It's clearly running a much more capable microcontroller than the Atmega328 (probably some ARM chip). And you don't have to program it to use it
Whether the arduino would be sufficient and appropriate for your purposes depends on what those are.
Well basically the project that i saw, used a PT and a CT on a three phase supply and then used NI USB 6009 to send the data over to the pc to be used in lab view. All other work was done in lab view.
What i have queries about is that can i still use an arduino to do the same task? Send the data right over to lab view? or is it gonna be way more trouble?
You can certainly get data from an arduino into labview. There is a lot of information on that online, sample code, etc. Just google it.