Agilent/Keysight U5404A

The Keysight U5404A is a remote switch probe adapter designed to extend the measurement capabilities of handheld digital multimeters. It connects directly to Keysight U1281A and U1282A DMMs, enabling single-button measurement acquisition and storage while maintaining excellent signal integrity across multiple test points. The adapter supports both 18 mm and 4 mm test probe interfaces and is rated for use in hazardous CAT III and CAT IV environments.

Technical Specifications

• Remote switch and adapter: CAT III 1000 V / CAT IV 600 V


• 18 mm test probes: CAT II 1000 V, 15 A


• 4 mm test probes (with conversion cap): CAT III 1000 V / CAT IV 600 V, 15 A Physical Characteristics


• Dimensions: 36.1 mm × 20.0 mm × 10.9 mm


• Weight: 9.5 g


• Operating temperature: 0°C to 55°C


• Storage temperature: -20°C to +75°C Interfaces and Connectors


• 4 mm banana plugs (×2)


• 18 mm test probe interface


• 4 mm test probe interface with conversion cap


• 2.54 mm pitch, 10-pin male header for signal output

Key Features

• Remote switch functionality for advanced control over multiple test points


• Compact, portable design optimized for field and bench work


• Single-touch measurement acquisition and storage capability


• Dual probe compatibility via interchangeable 18 mm and 4 mm interfaces


• CAT IV rated operation for critical installation environments


• Signal integrity optimization for accurate, repeatable results

Typical Applications

• Industrial electrical testing and troubleshooting


• HVAC and power distribution diagnostics


• Multi-point voltage and current measurement in CAT IV environments


• Handheld DMM probe extension for remote or confined measurement locations

Compatibility & Integration The U5404A integrates exclusively with Keysight U1281A and U1282A handheld digital multimeters. The 4 mm conversion cap enables standardized probe connectivity while maintaining CAT III 1000 V / CAT IV 600 V safety ratings. The 2.54 mm header interface provides signal routing flexibility for integration with external monitoring systems.