Conducting high frequency electrical measurements — Case study using a TASER M18 device

A number of measuring instruments are currently available for conducting dc and low frequency electrical measurements. However, to achieve a high degree of accuracy in high-voltage, high-frequency measurements for pulse power applications at low repetition rates requires careful adherence to established electrical procedures. Measurement errors may be introduced due to a variety of reasons. Parasitic elements may also play a significant role. The authors conducted a series of electrical tests to determine the output current waveforms and the power dissipated for a device operating at a high voltage and high frequency with a low duty cycle. The device of choice was a new TASER^® M18, used in the “drive-stun” mode and connected to eleven load resistances. Output current waveforms were recorded. The power dissipated in the various load resistances was also computed. The authors further compare their results with a series of measurements reported in the article, “Forensic Engineering Analysis of Electro-Shock Weapon Safety,” by James A. Ruggieri, P.E. This article was published by the Journal of the National Academy of Forensic Engineers, Vol. XXII, No. 2, December 2005, p. 19-48. In this article, Mr. Ruggieri reported his measurements of the electrical power outputs for the M18, alleging that as the output resistance decreased, the “Power Contributing Interval” (PCI) and consequently the output power, increased substantially. This paper also presents comparisons of the waveforms generated by the authors versus those presented by Mr. Ruggieri, and graphically compares the values of the calculated output power. This paper illustrates the importance of adhering to proper measurement techniques when conducting high-voltage, high-frequency measurements.