The Hioki CT6877 pass-through AC/DC current sensor is for use with Power Meters, Memory HiCorders and high performance Oscilloscopes. The CT6877 is a DC to 1 MHz/2000A sensor, ideal for evaluating the inverter power conversion efficiency in next generation devices. The CT6877 delivers a wide frequency band and excellent noise resistance, prerequisites for properly evaluating inverters motors used in electric vehicles and hybrid vehicles, a class of devices that continue to move toward ever larger currents and higher-frequency switching.

Most large currents are divided into two to four wires. In the past, it was necessary to measure wires individually using multiple current sensors due to the devices' insufficient aperture size and current ratings. The optional Sensor Unit CT9557 provided functionality for adding together the sensors' measured values in such setups and outputting the result as a single signal. Thanks to its large, 80 mm aperture, the CT6877 can accommodate four wires with an outer diameter of 31 mm (equivalent to a cross-sectional area of 250 mm2). In this way, a single sensor can be used to collectively measure wires carrying up to 2000 A.

Current sensor performance is maximized with the "Zero Flux (Fluxgate Detection)" measurement method. High frequency current is detected with windings (CT method), and direct to low frequency current is detected with fluxgates. Use of a newly developed opposed split coil* for the winding (CT) makes possible a broad measurement band, while strengthened shielding boosts anti-noise performance.

*Opposed Split Coil: Coil in which divided windings are arranged opposite each other on a magnetic core to broaden the range of current detection

The CT6877 has a frequency band of DC to 1 MHz, placing it among the best-performing pass-through sensors rated for 2000 A and making it ideal for measuring currents being switched at high frequencies by SiC/GaN elements.