Keysight / Agilent / HP E1476A High-Density Reed Relay Multiplexer Module

The Keysight/Agilent/HP E1476A is a high-density VXIbus reed relay multiplexer module engineered for automated test and data acquisition systems requiring precise multi-channel switching. This C-size, single-slot register-based module delivers thermocouple-compensated measurements, voltage acquisition, and resistance characterization across 64 temperature channels, 64 three-wire voltage channels, 64 two-wire resistance channels, and 32 four-wire resistance channels. Low-thermal offset reed relays (< 2 µV) ensure measurement integrity in demanding applications. The module's dynamically configurable architecture, dual-bank organization, and integrated analog bus support enable seamless integration into existing VXIbus systems. ## Technical Specifications • Module Type: Register-based VXIbus relay multiplexer, C-size form factor, 1-slot chassis requirement • Switching Technology: Reed relays with low-thermal offset < 2 µV • Channel Configuration: 64 thermocouple channels with automatic cold junction compensation; 64 three-wire voltage channels; 64 two-wire resistance channels; 32 four-wire resistance channels • Scanning Rate: 333 channels/s (typical) • Rated Load: 10⁷ operations • Reference Junction Accuracy: 0.38 °C (18–28 °C operating range) • Terminal Block: QUIC spring clamp with quick connect screwless terminals; accepts 22–26 AWG wire (0.5, 0.75, 0.9 mm) • Analog Bus Cable: 6 cm interconnect cable (E1400-61605) included ## Key Features • Dual-bank architecture with independent voltage sense and current source control switches • Three-wire and four-wire measurement support for precision resistance acquisition • Analog bus access via front panel connectors for external voltmeter/multimeter integration • Thermocouple temperature measurement with integrated cold junction compensation • High-integrity signal routing with separate high, low, and guard connections per channel ## Typical Applications • Multi-point thermocouple temperature monitoring • High-channel-count voltage data acquisition • Precision resistance characterization in production test • Automated thermal and electrical parameter measurement systems ## Compatibility & Integration Designed for VXIbus modular instrumentation systems with standard register-based control interface. Supports analog bus communication for interconnection with other VXI devices and compatible multimeters. Note: Product is marked obsolete by Keysight; service and support continue through end of worldwide support life.