HP Keysight Agilent E1421B VXI C-Size Mainframe Chassis

Description

Product Introduction

The HP Keysight Agilent E1421B is a compact, 6-slot C-size VXIbus mainframe designed for automated test equipment (ATE) applications where rack space is constrained. It houses high-density measurement, switching, and control modules while distributing system power and managing backplane timing signals across all installed instrument slots.

Engineered to operate reliably in dense industrial test racks, the E1421B features an integrated 450W power supply and variable-speed cooling fans that adapt directly to internal chassis thermal loads. Its rigid backplane delivers ultra-clean DC voltage rails and standardized VXI system lines (CLK10, TTL/ECL triggers, and VME interrupts) to preserve measurement integrity in high-precision test cells.

Key Technical Specifications

Application Scenarios & The “Trench” Experience

When a VXI test chassis fails, it rarely takes down just one instrument—it compromises the entire test bench. In our field experience, aging power supply capacitors or degraded cooling fans inside the E1421B cause intermittent voltage ripple on the backplane, triggering cryptic communication timeouts and false measurement failures across all six installed slots.

• Compact Aerospace Test Benches – Portable Flightline ATE – Provides a rugged, 6-slot enclosure for mobile radar and flight computer functional test sets.
• Automotive Line-End Testing – Sensor Calibration Stations – Houses switching matrices and high-speed DAQ modules in space-restricted manufacturing cells.
• Defense Electronics Maintenance – Intermediate Level (I-Level) Repair Racks – Delivers low-noise backplane power for sensitive RF and analog instrument modules.

Field Replacement Case: A commercial aviation repair facility hit a complete bottleneck when their primary avionics harness test bench suddenly lost power during a midnight shift. The internal +5V power rail on the 20-year-old E1421B chassis had failed due to dried-out filter caps. Swapping out the complete mainframe with a bench-tested surplus E1421B unit allowed the team to reinstall their original Slot 0 controller and DMM cards, restoring the test station in under 45 minutes without recalibrating individual instruments.

E1421B

Transparency SOP: Quality Assurance & Testing

We don’t just plug in an AC cord and check if the fan turns on; we load-test chassis backplanes under simulated operating conditions:

1. Inbound Mechanical Inspection: Inspect backplane DIN connectors, card guide alignment, fan blades, and power switch assemblies for physical damage.
2. DC Rail Voltage & Load Testing: Connect active load banks to verify that all seven DC output rails (+5V, ±12V, ±24V, -5.2V, -2V) maintain strict regulation under 80%+ rated load.
3. Ripple & Noise Evaluation: Measure AC ripple voltage on the DC supply outputs using an oscilloscope to ensure clean power delivery to sensitive analog modules.
4. Live System & Signal Verification: Seat an E1406A Command Module in Slot 0, execute full backplane self-tests, and verify 10 MHz CLK10 and trigger line continuity across all six slots.
5. Thermal Run & Final QC: Run the chassis continuously for 4 hours with temperature logging to confirm variable fan speed control before anti-static and shock-absorbent packaging.

The Veteran’s Tech Trap Guide (Crucial Value-Add)

• ⚠️ Backplane Pin Contamination: Before sliding any expensive C-size module into the chassis, inspect the backplane pins with a flashlight. Dust, lint, or bent pin fragments in an empty slot can short out the -5.2V ECL rail instantly upon main AC power-up.
• ❗ Airflow Blockage Traps: The E1421B uses pressurized side-to-side/bottom-to-top airflow. If you leave open, unshielded slots without installing blank VXI filler panels, cooling air will bypass adjacent high-power cards and cause local thermal shutdowns on adjacent modules.
• ⚠️ Dirty Fan Filter Maintenance: Over time, intake air filters collect shop-floor oil and dust. If the fan speed ramps up to maximum immediately upon startup, clean or replace the air filter right away before thermal stress degrades the internal 450W power supply module.
• ❗ System Power-Up Order: Always turn on the E1421B mainframe before or simultaneously with your host PC controller. Powering up the host PC while the VXI chassis is dark can cause PCIe/GPIB bus enumeration errors or freeze the interface card software.

Frequently Asked Questions (FAQ for Conversion)

Q: Can I mount B-size VXI modules in this C-size E1421B chassis?

A: Yes, but you must use physical C-to-B slot card adapters (such as HP/Agilent module card adapters) to properly seat and secure B-size cards onto the P1/P2 backplane.

Q: Is the power supply inside the E1421B field-replaceable?

A: Yes. The 450W power supply assembly can be removed and replaced as an integrated module, though the main AC cord must be disconnected and the chassis top cover removed first.

Q: Does the E1421B include built-in system monitoring?

A: Yes. The chassis includes internal sensors for over-temperature conditions and power supply voltage rail faults, which alert the system controller via backplane status lines.

Q: What is the difference between the E1421A and the E1421B?

A: The “B” revision features an upgraded auto-ranging power supply design, improved acoustic fan noise dampening, and better thermal dissipation efficiency under heavy module loads.

Q: How do you guarantee the condition of discontinued chassis surplus?

A: Every unit is fully disassembled for air-path cleaning, visually inspected, and validated with electronic load banks on all DC power rails before undergoing live slot testing. All sales include a full 12-month warranty.