delta scxi 1313

[Nandoman]

Hello

  I am working on a power quality analyzer using an scxi-1125 with an scxi-1313 voltage attenuator for metering voltage.  For current metering I have AC current to AC voltage transducers connected to the scxi-1313.  This has worked correctly so far for analyzing single-phase circuits.  I am planning to expand this application for three-phase circuits, and since I am using no PT's (Potential Transformers) for metering voltage but using the scxi-1125 attenuator instead, I was wondering if I could set the scxi-1125 inputs to read in differential mode and connect them in Y to get the phase voltage from a Triangle or Delta source (using the virtual neutral configuration) or an isolated Y source.
  Would this be safe for the equipment?? will it actually give me the phase voltages, or do I have to read the line-line voltages and then process them mathematically with LabVIEW to get the phase voltage??

Regards

Miguel

[Pedrobertoni]

Hello Nandoman.

 The advantage of using the 1125 is that your channels are isolated channels. You can keep on measuring your three lines independently and then, with labview, you can measure phase between lines. In fact, there are VIs that will help you do this. Check the link below to program phase measurement

http://digital.ni.com/public.nsf/allkb/F4BB644ECCA595D886256FFE00722E29?OpenDocument

This way, you are using efficiently your channels and you can use all the hardware resources independently for each of the signals.

Hava a nice day.