Hi,
The 6040E is a Data Acquisition board, and not a DMM, and can therefore not deliver data in RMS format, however, you can acquire the analog signal using the 6040E and then calculate the RMS value using one of your RMS Waveform Measurements VI's included with labview. You can find them at: Main Palette-> Analyze-> Waveform Measurements. If your application is not time critical (that is, if you can wait for the data to be acquired and then converted to RMS) this would be the most cost effective solution. If you need a faster response I recommend you check out our line of
Digital Multimeters.
The second issue you must be aware of is the input voltage. I'm aware that a lot of LEM's supply +-10V output, which would be OK, but if you have a LEM that provides a voltage greater than that you'd have to add signal conditioning to divide that voltage down. You can build your own amplifier, depending on the amount of noise you're dealing with, or check out some of our
signal conditioning products, that might help improve the acuracy of your measurement.
I hope all this information was useful. if you need anything else please contact us again.
Greetings
Daniel