Power choke testers simplify precision routine inductance and resistance tests

Saelig Company, Inc offers the ed-k DPG Power Choke Tester family. This family is a unique series of innovative measurement instruments for inductive power components, using currents up to 4kA and pulse energy up to 7.7kJ. The series utilises a large-signal impulse measuring method to offer a complete inductance curve as a function of the current L(i) or the applied time-voltage-integral L(∫Udt). This enables the saturation characteristics of a power inductor to be clearly seen swiftly. Other significant parameters are also offered, including incremental inductance and secant or amplitude inductance (the ratio of the winding flux linkage over winding current), and many other variables. The DPG10 enables investigations of very large inductors into the MVA range, yet it is also ideal for small PCB-mounted inductors. This covers precision measurements of a broad spectrum of inductive components down to the nH range.

The series also provides four internal resistance measurement ranges, with a resolution down to 10uOhm, and maximum measurable resistance of 35Ohm. A USB connection to a PC running the accompanying software simplifies routine tests in production areas or the individual laboratory tests. The software offers easy and intuitive operation through a user-friendly GUI, with measurement results displayed as diagrams and tables, pdf reports, data export, or data storage (XML, CSV).

The DPG10 uses proprietary internal electronics in the power stage, measurement amplifier, A/D converter, and microcontroller board to optimise them for specific purposes. Commercial current sensors, for example, are not suitable in terms of bandwidth, pulse strength, long-term stability and form factor. As a result, its devices are at the leading edge of technology, are compact, and offer excellent value. For measuring three-phase-inductors an extension unit is also available; the three windings are measured consecutively and automatically. For routine tests in mass production, the instrument can be integrated easily into automated test environments using a DLL or by LabView. The highly precise device is compact (18.5” x 19.7” x 6.7”) and weighs under 50lbs.

The series has been employed globally as a standard measurement instrument in the development, manufacture, and quality control of inductive power components such as solar, wind power, and UPS inverters, commutation equipment, PFCs, storage, line chokes for SMPS, and rotor and stator inductance. Due to its high current capability, this testing method has complemented and even replaced conventional LCR sine wave bridge methods in these applications.