CT6904A

Key Features

• Supports phase-shift correction when used with HIOKI power analysers
• AC/DC currents up to 500 A
• Frequency Bandwidth DC to 4 MHz (amplitude), DC to 1 MHz (phase)
• Basic accuracy 0.027 %
• 120 dB cmRR at 100 kHz
• Output voltage ratio 4 mV / A

The HIOKI CT6904A AC/DC Current Sensor is engineered for high-precision current measurements, supporting currents up to 500 A with a wide frequency bandwidth from DC to 4 MHz. Employing advanced zero-flux detection with flux gate technology, the sensor achieves exceptional linearity of ±5 ppm and a high common-mode rejection ratio of 120 dB at 100 kHz, ensuring accurate and reliable measurement even in noisy environments.

The CT6904A works directly with HIOKI Power Analysers and Memory Recorders, which supply power to the sensor via the ME15W connector. When combined with a HIOKI sensor unit (CT9555, CT9556, or CT9557), it can also be used with oscilloscopes or other DAQ systems, providing a voltage output ratio of 4 mV/A. Its robust construction, 32 mm (1.26 in) core diameter, 3-meter cable length, and maximum voltage rating of 1000 V CAT III ensure flexible installation and safe high-voltage operation across diverse applications.

The CT6904A delivers exceptional measurement accuracy, making it ideal for applications where precision is critical. It achieves a basic accuracy of ±0.025% of reading plus ±0.007% of full scale for DC measurements. For AC measurements, the basic accuracy is ±0.02% of reading plus ±0.007% of full scale. Combined with its wide frequency bandwidth, this performance ensures reliable results across both low- and high-frequency applications.

Compared to other current sensors on the market, the CT6904A minimises the impact of conductor position on measurement values, ensuring highly reproducible results. While the effect of conductor position typically becomes more significant at higher frequencies, the CT6904A effectively reduces this impact, delivering stable and reliable measurements. This high reproducibility is especially valuable when comparing the losses of multiple inductors or transformers, establishing the CT6904A as a top choice for loss measurements in such applications.

The CT6904A also supports phase shift correction functions of HIOKI Power Analysers, including the automatic correction function of the PW8001 Power Analyser. These features ensure precise power analysis in dynamic, high-frequency applications, making the sensor ideal for evaluating high-frequency inductor and transformer losses, wireless charging systems, and EV inverter motors.