Description
ABB AI845 3BSE023675R1 Product Description
Product Overview
ABB AI845 3BSE023675R1 is an 8-channel analog input module belonging to the ABB S800 I/O family. It is designed for single or redundant process-control applications and accepts 0–20 mA, 4–20 mA, 0–5 V and 1–5 V DC single-ended unipolar signals. The module provides 12-bit resolution and groupwise isolation from ground, making it suitable for reliable acquisition of transmitter and process-instrument signals in industrial automation systems.
The ABB AI845 3BSE023675R1 incorporates a current-limited, supervised transmitter supply for compatible 2-wire and 3-wire HART transmitters. Its HART pass-through capability allows HART communication information to be transmitted through the I/O architecture without requiring a separate analog interface. With a 10 ms update cycle, onboard diagnostics and support for redundant operation, AI845 3BSE023675R1 is well suited to ABB System 800xA, Freelance and S800-based DCS/PLC installations.
Technical Specifications
| Parameter | Specification |
|---|---|
| Product Model | AI845 3BSE023675R1 |
| Manufacturer | ABB |
| Product Family | S800 I/O |
| Product Type | Analog Input Module |
| Number of Channels | 8 |
| Input Type | Single-ended, unipolar |
| Current Input | 0–20 mA / 4–20 mA |
| Voltage Input | 0–5 V / 1–5 V DC |
| Resolution | 12 bit |
| Input Impedance, Voltage | >10 MΩ |
| Input Impedance, Current | 250 Ω |
| Maximum Error | ≤0.1% |
| Temperature Drift | ≤50 ppm/°C |
| Update Cycle | 10 ms |
| Input Filter Rise Time | 290 ms |
| HART Communication | Yes, pass-through |
| Redundancy | Supported |
| SOE | No |
| Transmitter Supply | Current-limited, supervised |
| Maximum Field Cable Length | 600 m |
| Rated Insulation Voltage | 50 V |
| Dielectric Test Voltage | 500 VAC |
| Power Dissipation | 3.5 W |
| Operating Temperature | 0 to +55°C |
| Protection Class | IP20 |
| Mounting | S800 MTU |
| Dimensions | 45 × 102 × 119 mm |
| Weight | Approx. 0.23 kg |
ABB specifies compatible MTUs including TU810, TU812, TU814, TU818, TU830, TU833, TU835, TU838, TU844, TU845 and TU854.
Main Features and Advantages
8-Channel Flexible Analog Acquisition
The ABB AI845 3BSE023675R1 provides eight analog input channels that can be configured for standard industrial current or voltage signals. Supporting both 4–20 mA/0–20 mA and 1–5 V/0–5 V makes it practical for process transmitters, signal conditioners and conventional analog instruments.
AI845 3BSE023675R1
HART Pass-Through Communication
A major advantage of AI845 is its integrated HART pass-through capability. In compatible configurations, the same field connection can carry the conventional analog process value while allowing HART digital information to pass through the I/O system. This simplifies access to transmitter diagnostics and configuration information.
Redundant Operation
The module supports both single and redundant operation, allowing it to be integrated into architectures where higher I/O availability is required. This makes AI845 particularly useful for continuous-process installations where loss of an analog measurement channel can affect process visibility or control.
Supervised Transmitter Power
The module distributes external HART-compatible transmitter supply to individual channels and incorporates current limiting and supervision. This simplifies connection of compatible 2-wire and 3-wire transmitters while providing additional protection against abnormal field-current conditions.
Fast Update and Stable Measurement
With a specified 10 ms update cycle, 12-bit resolution and maximum error of 0.1%, AI845 provides a practical balance between measurement resolution, response time and system integration for conventional process instrumentation.
Advanced Diagnostics
The module performs diagnostics on internal electronics and field-related conditions, including analog readback, reference voltage, internal power supply, watchdog, memory and channel-related functions. Front LEDs provide fault, run and warning indications, helping maintenance personnel locate problems quickly.
Industrial Environmental Capability
The module is designed for S800 industrial I/O installations and supports certifications including ATEX Zone 2, C1 Zone 2/C1 Division 2, as well as marine certifications from BV, DNV and LR. This broad certification coverage expands its suitability for process, marine and industrial environments.
Application Fields
ABB AI845 3BSE023675R1 is primarily used in DCS, PLC and process-automation systems for acquiring analog signals from field transmitters. Typical measurements include pressure, flow, level, temperature converted to 4–20 mA, and other continuous process variables.
In oil and gas facilities, AI845 can interface with pressure, flow and level transmitters installed around separators, compressors, pipelines, storage systems and process units. HART pass-through provides additional access to intelligent transmitter information while retaining the standard analog process-value channel.
In chemical and petrochemical plants, the module can collect 4–20 mA signals from reactors, pumps, heat exchangers and distillation equipment. Redundant operation is particularly valuable in continuous processes where maintaining measurement availability is important for control and monitoring.
In power generation, AI845 3BSE023675R1 can acquire analog signals from auxiliary systems, water/steam processes, fuel systems and balance-of-plant equipment. Its diagnostics and HART functionality can assist maintenance teams in identifying transmitter and I/O problems without unnecessarily interrupting operation.
The module is also suitable for metallurgy, pulp and paper, water treatment, pharmaceutical manufacturing, marine applications and general smart manufacturing. Its 600 m maximum field-cable length and compatibility with numerous S800 MTUs make it practical for distributed field instrumentation.
Related Products
- AI830 3BSE013228R1 — S800 analog input module for temperature and analog measurement applications; suitable where different sensor types are required.
- AI835 3BSE008520R1 — Related S800 analog input module for process measurement with a different channel/configuration architecture.
- AI840 3BSE020848R1 — Related 8-channel S800 analog input module for standard process signals.
- AI845 3BSE023675R1 — 8-channel HART-capable analog input module, supporting 0/4–20 mA and 0/1–5 V signals; the main product described above.
- AI880A 3BSE039293R1 — S800 high-integrity analog input module for applications requiring enhanced safety-related functionality.
- AI890 3BSC690071R1 — 8-channel analog input module designed for 0–20 mA signals and intrinsic-safety applications.
- AI893 3BSC690141R1 — S800 analog input module for RTD and thermocouple signals, suitable for direct temperature measurement.
- TU844 — Compatible S800 Module Termination Unit that allows individual AI845 channels to be configured for voltage or current inputs.
- TU845 — Alternative compatible MTU supporting the flexible channel configuration of AI845.
- TU830 / TU833 — S800 termination units compatible with AI845 for different cabinet and field-wiring arrangements.
