Process Analytics Overview
The B&R X20AI2437 (X20AI2437) is a high-precision 2-channel isolated analog input module purpose-built for the modular X20 automated environment. Deployed across high-reliability process sectors like oil and gas refining, chemical manufacturing, and heavy offshore marine platforms, this module interfaces with critical process instrumentation. By measuring transmitter telemetry with single-channel galvanic isolation, the unit ensures high noise immunity, eliminates ground loop interference, and ensures continuous uptime for critical closed-loop control applications.
Converters and Channel Power Distribution
This analog card contains two differential inputs that can be configured independently via software to handle either 4 to 20 mA or 0 to 25 mA current loops. The system integrates an on-board, short-circuit-proof sensor power supply for each channel that delivers a stable 25 VDC output up to 30 mA to power external field transmitters. Utilizing a 15-bit digital converter resolution with standard INT output formatting, the module includes B&R NetTime microsecond timestamping capability to synchronize analog data acquisition directly with system-wide motion control cycles.
Technical Performance Matrix
| Core Parameter |
Functional Specification |
| Model |
X20AI2437 |
| Brand |
B&R Automation |
| Origin |
Austria |
| Input Count |
2 differential analog inputs |
| Input Signal Range |
4 to 20 mA or 0 to 25 mA (Software selectable) |
| Isolation Design |
True single-channel isolation barriers |
| Converter Resolution |
15-bit digital conversion |
| Data Sampling Speed |
4.7 to 960 samples per second (Adjustable) |
| Integrated Transmitter Power |
25 VDC (±2% tolerance), Max. 30 mA per channel |
| Overload Protection |
Continuous short-circuit proof output |
| Raw Output Formatting |
Signed 16-bit Integer (INT) |
| Atmospheric Tolerance |
5 to 95% Relative Humidity (Non-condensing) |
| Weight |
0.09 kg (Net) / 2.0 kg (Shipping gross) |
Industrial Maintenance and FAQs
How do you configure the module to change the sampling rate from 4.7 to 960 samples per second?
Open the physical hardware topology interface within B&R Automation Studio, select the target X20AI2437 slot, and navigate to the I/O configuration tab. Modifying the data output rate directly adjusts the internal digital filter; lower sampling rates increase overall signal noise rejection, while higher rates maximize transient response speed.
What happens to the channel if an external field instrument develops a direct short circuit?
The integrated 25 VDC transmitter power supply features an electronic short-circuit protection mechanism. If an overload occurs, the supply limits the current to a maximum of 30 mA indefinitely. The affected channel shuts down its measurement loop to prevent hardware damage, while the adjacent channel continues operating without interruption.
Does this module require external loop power supplies for standard 2-wire transmitters?
No. The X20AI2437 eliminates the need for auxiliary power distribution blocks by providing an independent, isolated 25 VDC supply rail directly on the terminal block for each channel to energize the loop.
Field Commissioning and Wiring Guidelines
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Differential Signal Terminal Connections: Connect the signal return paths strictly across the designated differential positive (+) and negative (-) terminals. To utilize the integrated loop power supply, route the 25 VDC output to the transmitter's positive input, and return the 4 to 20 mA loop back to the module's positive input terminal.
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Shield Grounding and NetTime Integrity: Land instrument cables using high-density shielded twisted pairs. To ensure the microsecond accuracy of the NetTime function, ground the shield at the terminal base using an official X20 shield bus attachment, ensuring low-impedance grounding directly to the control panel sub-panel.
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Preventing Condensation in Remote Panels: Maintain standard operating conditions with relative humidity restricted between 5 and 95% non-condensing. If installing the rack inside remote field boxes exposed to shifting ambient temperatures, install internal panel anti-condensation strip heaters to protect the isolated electronic components from moisture tracking.