Keysight / Agilent / HP E1501A 8-Channel Direct Input SCP Module

The Keysight/Agilent/HP E1501A is an 8-channel direct input Signal Conditioning Plug-on (SCP) module for VXI system integration. It buffers voltage signals without modification and routes them directly to the VXI backplane, delivering measurement bandwidth exceeding 100 kHz. The module excels in data acquisition environments requiring reliable signal conditioning and protection. Built-in overvoltage protection safeguards inputs against peaks up to ±16 V during normal operation, with damage ratings beyond ±42 V peak. Open Transducer Detection (OTD) can be enabled per channel to identify open circuits by injecting small currents and monitoring for over-voltage conditions. Input impedance exceeds 100 MΩ differential, minimizing loading effects on source signals. Voltage measurement ranges span ±62.5 mV to ±16 V full scale, with fixed x1 gain and no built-in filtering for direct signal paths. Accuracy depends on the coupled scanning A/D converter - typical performance on the 0.0625 V range reaches 0.01% ± 5.3 µV, while the 16 V range achieves 0.01% ± 488 µV. Autoranging adds ±0.02% FS to stated accuracy. Maximum tare calibration offset varies by A/D range and SCP gain. The E1501A accommodates voltage measurements, temperature sensing via thermocouples, resistance measurements, strain gauge signals, and general voltage output sensors. Temperature measurement accuracy using Type E thermocouples ranges from 2.25°C across -200 to 0 °C down to 0.22°C in the 400 to 800 °C band; add transducer accuracy to determine total error.

Technical Specifications

Channels: 8

Input Type: Direct input

Bandwidth: >100 kHz

Voltage Measurement Ranges (Full Scale): ±62.5 mV to ±16 V

Input Impedance: >100 MΩ differential

Gain: Fixed x1

Input Over-voltage Protection: ±16 V peak operating; >±42 V peak damage rating

Open Transducer Detection: Per-channel enable; detects open circuits via current injection

Tare Calibration Offset: Maximum values depend on A/D range and SCP gain (example: 5.3 µV on 0.0625 V range)

Typical Accuracy (with A/D filter ON): 0.01% ± 5.3 µV (0.0625 V range); 0.01% ± 488 µV (16 V range); add ±0.02% FS with autoranging enabled

Key Features

Direct signal path without filtering

Per-channel OTD capability

High input impedance minimizes transducer loading

Multi-range voltage measurement architecture

Transient and overvoltage suppression

Typical Applications

Voltage measurements

Temperature sensing (thermocouples)

Resistance measurement

Strain gauge acquisition

General voltage output sensor interfacing

Compatibility & Integration Operates with E1413C 64-Channel Scanning A/D Converter, E1415A Algorithmic Closed Loop Controller, and E1419A Multifunction Measurement and Control Module (SCP positions 5–8).