New-Tech Europe Magazine | Jan 2018

include the phase relationships between the different harmonics as well as the total harmonic distortion (THD). The R&S Scope Rider provides these measurement functions thanks to its harmonics analysis function. Up to four channels can be simultaneously and automatically evaluated, displayed and monitored with respect to predefined limits if necessary. In order to provide maximum safety for hazardous test situations, the R&S Scope Rider (R&S RTH) can be remotely operated via WLAN to fully decouple test instrument operation from the DUT. Summary Developers have already come to appreciate oscilloscopes with isolated input channels as a powerful yet cost-effective alternative for safely performing measurements on power electronics modules. Thanks to advanced frontend technology, up to 500 MHz bandwidth and powerful signal processing,

Fig. 7: Automatic measurement functions calculate the apparent, active and reactive power as well as the power factor from the measured voltage (channel 1) and current (channel 2); source: Rohde & Schwarz

these oscilloscopes are now also appropriate for measurements on circuits with GaN- or SiC-based semiconductors. The R&S Scope Rider from Rohde & Schwarz is an impressive representative of this class and is also well suited for classic

oscilloscope applications due to its wide range of analysis capabilities. Author: Dr. Markus Herdin is product manager for oscilloscopes at Rohde & Schwarz in Munich. More information: www.rohde-schwarz.com/rth.

Fig. 8: Harmonics analysis of a three-phase 100 V signal. The blue lines show the current limit value in line with EN 50160. The 13th harmonic and its characteristics are highlighted; the highlighted levels for the three channels lie between –56.5 dB and –51.0 dB; source: Rohde & Schwarz

Fig. 9: In especially hazardous test situations, the R&S Scope Rider can be remotely operated via WLAN; source: Rohde & Schwarz

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