ProDAQ 6131 Isolated Precision RTD Input LXI Instrument

High-accuracy RTD temperature measurement for demanding environments

Accurate temperature measurement is a fundamental requirement in cryogenic research, aerospace qualification, propulsion test benches, energy systems, and industrial R&D. In these environments, engineers rely on sensors to measure correctly, even when exposed to harsh electrical noise, extreme thermal swings, or distributed grounding conditions.

The ProDAQ 6131 Isolated Precision RTD Input LXI Instrument is engineered specifically to address these challenges. With 32 fully isolated RTD/resistance measurement channels, 24-bit Sigma-Delta ADCs, programmable pulsed excitation, and LXI-based connectivity, it delivers reliable, high-resolution thermal data across complex test architectures.

What makes the ProDAQ 6131 different?

Most RTD measurement systems compromise of either channel density, electrical isolation, or sampling accuracy. The ProDAQ 6131 is designed to maximise all three:

• 32 isolated channels (channel-to-channel and channel-to-chassis isolation up to 300 VDC)
• True simultaneous sampling, due to a dedicated ADC per channel
• Programmable pulsed excitation for stable and repeatable RTD measurements
• Scalable network-based LXI architecture with IEEE-1588 synchronisation
• Redundant Ethernet ports and redundant power supplies for high-availability

These capabilities make the ProDAQ 6131 a fit for high-integrity temperature acquisition across large channel counts and distributed systems.

Key technical features

High-accuracy RTD measurement

• Supports Pt-100, Pt-500, Pt-1000 and other resistive devices
• 24-bit Sigma-Delta ADC on every channel
• Up to 1000 S/s sampling rate with true simultaneous sampling
• <100 µV RMS noise, aided by per-channel EMI filtering
• Built-in software linearization and calibration options

This combination allows the 6131 to achieve full-scale accuracy typically better than 0.003%, even under electrically noisy conditions.

Advanced per-channel excitation control

• Individually programmable 2 to 2 mA pulsed excitation
• ≤0.01% excitation stability over 24 hours
• Designed to reduce self-heating effects in RTDs
• Enhanced measurement repeatability over long-duration tests

Robust electrical isolation

High-density temperature measurement systems often suffer from:

• Ground loops
• Common-mode noise
• Cross-channel interference

Each ProDAQ 6131 channel is fully isolated from every other channel and from the chassis.

This ensures measurement integrity even when sensors are distributed across large metal structures, vacuum chambers, or insulated cryogenic assemblies.

Integrated analogue outputs

A unique feature among RTD measurement instruments is the dual 0–10V buffered outputs per channel.

• Short-circuit protected
• Low output resistance (≤1 Ω)
• Reproducing sensor profiles for system validation
• This output can reproduce the measured signal either as resistance or temperature

Flexible system integration

The ProDAQ 6131 is designed for large-scale test stands:

• IEEE-1588 Precision Time Protocol for multi-device synchronisation
• SCPI/VXI-11 interface for seamless integration via the VISA I/O library
• Direct streaming to one or multiple servers
• Built-in web interface for configuration and monitoring
• Redundant power supplies (85–264 VAC each) and redundant Ethernet ports

This architecture supports both standalone and distributed system topologies.

Applications where the ProDAQ 6131 excels

Cryogenic test facilities

Cryogenic measurements demand:

• High resolution
• Low noise
• Stable excitation
• Minimal thermal loading

The ProDAQ 6131’s low-noise 24-bit ADCs and pulsed excitation make it ideal for monitoring:

• Liquid hydrogen or methane feed system temperatures
• Cryogenic tank stratification
• Thermal gradients during engine cooldown cycles

Aerospace and propulsion test stands

Aerospace test environments require reliable measurement under vibration, EMI, and rapid transients.
The 6131 provides:

• Simultaneous sampling for accurate thermal mapping
• Channel isolation to eliminate aircraft/engine grounding issues
• High sampling rates for dynamic events like ignition or load changes

Industrial and energy systems

From power-plant monitoring to high-power electronics testing, the 6131 supports:

• Long-term reliability
• Distributed architecture
• Rugged isolation requirements
• High channel counts without synchronisation drift

Why engineers choose the ProDAQ 6131

• Extremely high measurement accuracy
• Excellent channel-to-channel isolation
• True simultaneous sampling
• Network-based, scalable LXI architecture
• Redundant power & Ethernet improve uptime
• Integrated analogue outputs (rare for RTD instruments)
• Flexible deployment options

To integrate the ProDAQ 6131 into your thermal measurement architecture, speak with Bustec’s engineering team:
👉 www.bustec.com/contact/