Its shielding technique, using a low sensitivity coil and low-noise signal-conditioning circuitry, gives the wide-band screened CWT Mini probe improved immunity to local dV/dt transients while maintaining small size, flexibility, and 3dB bandwidth of up to 30 MHz for a 100 mm coil. The probes feature a coil 4.5 mm thick with 5 kV insulation voltage, and can handle maximum current slope of 70 kA/µsec.
The enhanced accuracy of a screened probe is required for applications such as measuring complex current waveforms in equipment such as UPS circuits, switched-mode power supplies and Variable-Speed Drive (VSD) inverters where high power density leads to high field strengths, or where the high speeds and high blocking voltages of silicon-carbide (SiC) devices call for higher probe bandwidth and better common-mode immunity.
The CWT Mini probes eliminate the extra bulk and bandwidth restrictions imposed by conventional screening techniques, while delivering the known advantages of a Rogowski coil. These include zero insertion impedance, freedom from flying leads, isolated measurement, high peak-current rating, and the ability to measure small AC currents in the presence of large DC current.