Agilent/Keysight N2780B

The Keysight N2780B is an AC/DC current probe that combines Hall effect sensing with AC current transformer technology to deliver simultaneous DC and AC current measurements from 20 mA to 500 Arms continuous operation. Built for power electronics characterization, the probe operates across a DC to 2 MHz bandwidth with ±1.0% amplitude accuracy (typical) and can handle peak currents up to 700 A and input voltages to 600 V CAT2. Its hybrid architecture eliminates the measurement dead zones inherent in transformer-only designs, capture the complete current signature in motor drives, power supplies, inverters, and switching controller circuits.

Technical Specifications

• Bandwidth: DC to 2 MHz


• Current Range: 20 mA minimum; 500 Arms continuous (RMS); 700 A peak


• Amplitude Accuracy: ±1.0% of reading (typical), ±500 mA offset (typical)


• Noise: 2.5 mArms (typical)


• Maximum Input Voltage: 600 V CAT2


• Maximum Conductor Diameter: 20 mm


• Output Connector: High impedance BNC


• Power Requirement: 12 VDC external supply (Keysight N2779A recommended; supports up to three N278xB probes per supply unit)


• Power Consumption: 7.2 VA maximum (at rated current)

Key Features

• Hybrid Hall effect and current transformer technology for DC and AC measurement


• Wide dynamic range with flat frequency response across the measurement band


• Low insertion loss and high signal-to-noise ratio


• Demagnetize button to eliminate residual core magnetism


• Zero adjustment dial for offset and temperature drift correction

Typical Applications

• Switching power supply design and validation


• Motor drive and controller characterization


• Inverter testing and efficiency analysis


• Disk drive, LCD display, and electronic ballast current profiling


• Current amplifier load testing

Compatibility & Integration The N2780B interfaces with Keysight oscilloscopes via high-impedance BNC input. Compatible with 1000, 2000 X-Series, 3000 X-Series, 4000 X-Series, 5000, 6000, 7000, 8000, and 9000 Series instruments. Infiniium 90000A Series requires Keysight E2697A adapter; 90000 X-Series requires N5449A adapter. Set oscilloscope input impedance to 1 MΩ for accurate measurements.