Power Analyzer suppliers has united the real time performance of an oscilloscope with all the precision of an energy analyzer. The purpose is to capture voltage and current waveforms with higher precision, so as to recognize those difficult-to-spot passing signals that could disappear in a fraction of a moment. 

The matter about transients is that they are simply that -- passing -- they vanish from the display almost the moment they look. The Power Analyzer Order has a consistently active background function which lists the previous 1000 waveforms, which means that you can remember them at any opportunity to search for anything strange, even hunting them according to requirements. You might even use a saved waveform to redefine activate requirements.