Product Apr. 26, 2016

Hioki Launches AC Clamp Meter 3280-20F

Instrument Accurately Measures Even Distorted Waveforms

April 26, 2016 - Nagano, Japan

Hioki is pleased to announce the launch of the AC Clamp Meter 3280-20F (featuring true RMS measurement) and the AC Clamp Meter Set 3280-90F, which includes the new sensor as well as the AC Flexible Current Sensor CT6280, which was launched this February.

Technicians maintaining electrical equipment in buildings and manufacturing plants need to measure current and voltage. For many years, Hioki has supplied clamp-on current meters used in the field to carry out such electrical work.

The 3280-20F performs true RMS AC measurement, enabling it to accurately measure waveforms that are distorted due to use of inverter-equipped devices or switching power supplies.

3280-20F Features
1. True RMS measurement to enable accurate measurement of currents, even when the waveform is distorted
There are two methods for measuring AC currents: the mean-value method and the true RMS method. Both methods can accurately measure current that takes the form of a distortion-free sine wave, but the mean-value method is incapable of accurate measurement when the waveform is distorted due to use of inverter-equipped devices or switching power supplies. A clamp meter with true RMS measurement capability is required in order to accurately measure current under such conditions. Since the 3280-20F supports true RMS measurement, it can accurately measure current even when the waveform is distorted.

2. Operation under a broader array of conditions thanks to an expanded operating temperature range
The 3280-20F features an expanded operating temperature range. Whereas previous products had an operating temperature range of 0°C to 40°C, the 3280-20F’s range has been expanded to -25°C to 65°C. As a result, the instrument can be used in a variety of climates worldwide, from cold regions with subzero temperatures to areas of extreme heat in excess of 40°C.

3. Easy measurement of tangled wires when used with a flexible current sensor
As distribution panels have become smaller in recent years, technicians have increasingly found themselves faced with tangled wiring. As a result, it is becoming difficult to measure wires with the low-profile, jaw-type clamp (clamp-on current sensor) typically used in previous products. To address this issue, Hioki developed the AC Flexible Current Sensor CT6280 as an option and launched it this February. The CT6280’s flexible design makes it possible to affix the sensor in locations where measurement with a rigid jaw would not be possible. In addition, the small cross-sectional diameter of the CT6280’s cable, which at 5 mm is thinner than that of competing products, makes it easy to affix in measurement locations where wires are tangled together. Furthermore, the CT6280 can measure large currents of up to 4199 A.

Hioki 3280-20F Product Line
3280-20F (featuring true RMS measurement)
3280-90F (set of 3280-20F and AC Flexible Clamp Sensor CT6280)

About Hioki

Established in 1935, HIOKI E.E. CORPORATION (TSE: 6866) has grown to become a world leader in providing consistent delivery of test and measuring  instruments through advanced design, manufacturing, and sales and services. By offering over 200 main products characterized by safety and quality while meeting an expansive range of applications, we aim to contribute to the efficiency and value of our customers' work in research and development, production and electrical maintenance. HIOKI products and services are available around the world through our extensive network of subsidiaries and distributors. Information about HIOKI is available at

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Hioki 3280-20F AC Clamp Meter