Keysight (Agilent) 34405A Digital Multimeter 5 1/2 Digits

The Keysight 34405A is a 5 1/2 digit digital multimeter delivering 120,000 counts of resolution for precision DC, AC, resistance, and specialized measurements across R&D, manufacturing, design validation, and educational environments. Built around a dual VFD display, it provides simultaneous readings with DC voltage accuracy of 0.025% and supports 16 built-in measurement functions including temperature, capacitance, diode test, and continuity. The instrument accommodates AC and DC current up to 12 A, frequency measurement to 750 V input, and temperature sensing from −80 °C to 150 °C using standard thermistor sensors. Six integrated math functions—Null, dBm, dB, Min/Max, Limit, and Hold—enable post-measurement data manipulation without external tools.

– Technical Specifications

DC Voltage: 100 mV to 1000 V at 0.025% accuracy; 10 MΩ input impedance with <120 pF parallel capacitance.

AC Voltage (True RMS): 100 mV to 750 V; 0.2% + 0.1% accuracy (45 Hz–10 kHz); 3 maximum crest factor at full scale; 20 Hz to 10 kHz frequency response.

DC Current: 10 mA to 12 A with shunt resistance from 0.1 Ω to 10 Ω across 10 mA to 1.2 A ranges.

AC Current (True RMS): 10 mA to 10 A; 0.5% + 0.1% accuracy (45 Hz–1 kHz); 20 Hz to 1 kHz frequency response.

Resistance: 2-wire measurement from 100 Ω to 100 MΩ; 0.05% + 0.008% accuracy (100 Ω range with Math Null).

Frequency: 100 mV to 750 V measurement range; 0.18% + 0.003% accuracy (<2 Hz ranges).

Temperature: −80 °C to 150 °C via 2-wire ohms measurement of 5 kΩ thermistor sensors (YSI 4407).

Capacitance: 1 nF to 10,000 µF; 2.0% + 0.8% accuracy (1.000 nF range).

Diode Test & Continuity: Diode mode uses 0.83 mA ± 0.2% constant current source with <5 V open circuit voltage; continuity fixed at 10 Ω threshold.

– Key Features

• Dual VFD display for simultaneous parameter monitoring
• Reading rates to 19 readings/sec (DCV, DCI, ACV, ACI at 4.5 digits); 9 readings/sec for frequency
• USB 2.0 interface with TMC-488.2 compliance for automated testing and data logging
• Industry-standard SCPI command set for remote instrument control
• Shock-absorbing bumpers for field durability
• Compliance with major safety and regulatory standards

– Typical Applications

• Component and module validation in design verification workflows
• Production test and incoming component acceptance
• Laboratory measurement and characterization
• Educational electronics and electrical engineering instruction

– Compatibility & Integration

USB 2.0 connectivity supports Keysight IO Library Suite and DMM Intuilink software for data acquisition, logging, and analysis workflows without additional hardware adapters.