Agilent/Keysight N2791A

The Keysight N2791A is a 25 MHz differential probe engineered for floating signal measurements on earth-grounded oscilloscopes. It enables safe, accurate acquisition of differential and common mode signals up to ±700 V, making it ideal for power electronics characterization and circuit analysis where conventional single-ended probes are inadequate. This probe features user-selectable 10:1 or 100:1 attenuation, allowing flexible dynamic range optimization across measurement scenarios.

At 100:1 attenuation, maximum differential operating voltage reaches ±700 V; at 10:1, ±70 V. Common mode voltage is rated to ±700 V across both settings. The 1000 Vrms CAT II working voltage rating between input leads and earth ensures safe operation in industrial and lab environments.

Technical Specifications

• Bandwidth: 25 MHz


• Attenuation: User-selectable 10:1 or 100:1


• Maximum Differential Voltage: ±700 V (100:1), ±70 V (10:1)


• Maximum Common Mode Voltage: ±700 V


• Input Impedance: 8 MΩ


• Input Capacitance: 8 pF


• Rise Time: ≤ 14 ns


• Common Mode Rejection Ratio: > 50 dB at 1 MHz


• CAT Rating: II, 1000 Vrms maximum working voltage

Key Features

• Battery-powered operation (4× AA cells included) with optional USB power via supplied 2 m cable


• LED power status indicator and over-range alert for dynamic range monitoring


• 70 cm BNC output cable compatible with any 1 MΩ oscilloscope input


• 45 cm input lead length with safety hooks and alligator clips


• Compact form factor: 170 mm × 63 mm, 400 g


• Operating temperature range: −10 to 40 °C

Typical Applications Power supply characterization, motor drive analysis, switching circuit evaluation, isolated signal measurement in multi-channel systems, and DC-link voltage monitoring in power conversion topologies.

Compatibility & Integration Connects directly to any oscilloscope with 1 MΩ BNC input, including Keysight InfiniiVision 30 series. AutoProbe interface compatible on scope models supporting this standard.