ABB AI835A

Description

Detailed Parameter Table

ABB AI835A

Product introduction

The AI835A is a high-density analog input module from ABB, designed to efficiently capture multiple analog signals from field devices and convert them into digital data for the AC800M controller in industrial automation systems. As a versatile member of the S800 I/O family, it serves as a “multi-sensor interface” for applications requiring simultaneous monitoring of various process variables, such as temperature, pressure, and flow, in medium-precision scenarios.

This module integrates seamlessly with ABB’s AC800M controller and relies on terminal bases like the TB820V2 for secure wiring to field devices. With 8 configurable channels supporting a wide range of signals (from 4-20 mA transmitters to thermocouples and RTDs), the AI835A is ideal for applications that balance channel quantity with reliable performance, such as chemical processing plants, water treatment facilities, and medium-scale manufacturing lines.

Built with industrial-grade components, the AI835A features robust isolation and wide temperature tolerance, ensuring stable operation in harsh industrial environments. Its 16-bit resolution and 50 Hz sampling rate make it suitable for capturing steady-state and moderately dynamic process variables. Unlike the AI930 (which prioritizes high precision and speed), the AI835A focuses on high channel density, providing a cost-effective solution for systems requiring multiple analog inputs.

Core advantages and technical highlights

High channel density

The AI835A offers 8 channels in a compact 22 mm width, maximizing space utilization in control cabinets. In a water treatment plant, for example, it can monitor 8 different parameters (such as pH levels, turbidity, and flow rates) using a single module, reducing the number of modules needed compared to lower-channel alternatives. This high density lowers overall system costs and simplifies wiring, making it ideal for applications with numerous analog sensors.

Versatile signal compatibility

Each of the AI835A‘s 8 channels can be independently configured for different signal types, allowing mixed-use in complex systems. For instance, in a food processing plant, one channel can measure oven temperature via a type K thermocouple, another can monitor pressure via a 4-20 mA transmitter, and the remaining channels can track various flow rates via 0-10 V sensors—all on a single module. This versatility eliminates the need for multiple specialized modules, streamlining system design.

Reliable performance

With ±0.1% accuracy (at 25°C) and 16-bit resolution, the AI835A delivers consistent measurements for medium-precision applications. In a chemical processing plant, it can monitor reactor pressure with sufficient accuracy to ensure process safety and product quality. The module’s 2.5 kV AC isolation prevents ground loops and electromagnetic interference, ensuring stable readings even in electrically noisy environments.

Efficient data acquisition

The AI835A‘s 50 Hz sampling rate is well-suited for capturing moderately dynamic process variables, such as temperature changes in a heating chamber or flow rate fluctuations in a pipeline. This sampling rate balances data freshness with system bandwidth usage, ensuring that the AC800M controller receives timely information without being overwhelmed by excessive data.

ABB AI835A

Typical application scenarios

In a chemical processing plant, the AI835A is used to monitor multiple parameters in a batch reactor system. Connected to the TB820V2 terminal base, it measures:

• Reactor temperature via Pt100 RTDs
• Pressure via 4-20 mA transmitters
• Level via 0-10 V sensors
• Flow rates of various chemicals via 4-20 mA flow meters

The module transmits this data to the AC800M controller, which uses the information to adjust heating elements (via AO801 modules) and control valves (via DO910 modules) to maintain optimal reaction conditions. The AI835A‘s 8 channels allow all these parameters to be monitored from a single module, simplifying cabinet design and reducing wiring complexity.

In a medium-sized manufacturing facility, the AI835A integrates with the CI810B Profibus module to transmit analog data to a SCADA system. It monitors temperature, pressure, and vibration levels of various machines, providing operators with real-time process visibility. If a parameter exceeds its threshold, the SCADA system triggers an alarm via the DO910 module, enabling timely intervention to prevent equipment damage.

Related model recommendations

• AI930: A high-performance analog input module with 4 channels, offering higher accuracy (±0.05%) and faster sampling rates (up to 500 Hz) for applications requiring precision beyond the AI835A‘s capabilities.
• TB820V2: A terminal base that provides secure wiring connections for the AI835A, enabling plug-and-play installation and shielded sensor connections.
• AO801: An analog output module that works with the AI835Ain closed-loop control systems—e.g., adjusting a valve based on flow readings from the AI835A.
• CI810B: A Profibus DP module that integrates AI835Adata into Profibus networks, facilitating communication with SCADA systems and other control devices.
• DO910: A digital output module that, when paired with the AI835A, activates alarms or control devices based on threshold crossings of measured parameters.
• 3BHE009017R0102: A power supply module that delivers stable 24 V DC to the AI835Aand terminal base, ensuring reliable operation.

Installation, commissioning and maintenance instructions

Installation preparation

Before installing the AI835A, ensure the control cabinet is clean, dry, and free from conductive debris. The ambient temperature must be within -25°C to +70°C, with relative humidity ≤95% (non-condensing). Required tools include a torque screwdriver, wire strippers, and a calibration tool (for commissioning).

Mount the TB820V2 terminal base on a 35 mm DIN rail, then plug the AI835A into the base until it clicks into place. Use shielded twisted-pair cables (0.5-1.5 mm²) for sensor connections, with shields grounded at both ends to minimize noise. Separate high-voltage wiring from low-voltage sensor cables by at least 100 mm to avoid interference.

Connect the 24 V DC power supply (from 3BHE009017R0102) to the terminal base, verifying polarity. Configure channel types, ranges, and filtering via the AC800M controller software before powering on.

Commissioning steps

After installation, calibrate the AI835A using a precision calibrator. For each channel:

1. Apply a 0% span signal (e.g., 4 mA for a 4-20 mA input) and record the reading.
2. Apply a 100% span signal (e.g., 20 mA) and verify accuracy within ±0.1%.
3. Test mid-range values to ensure linearity.

For thermocouple channels, verify cold-junction compensation accuracy using a reference thermometer. Configure sampling rates based on application needs—use the default 50 Hz for most steady-state processes, and adjust if necessary for moderately dynamic variables.

Maintenance suggestions

For daily maintenance, check the AI835A‘s LEDs: a steady green power LED and flashing green channel LEDs indicate normal operation. A red fault LED signals issues like open circuits or overrange signals—refer to the user manual for channel-specific codes.

Calibrate the module annually (or semi-annually in more critical applications) using a certified calibrator. This ensures that measurements remain accurate over time, especially in regulated industries.

Inspect terminal connections quarterly for corrosion or looseness, which can introduce measurement errors. Clean the module with compressed air to remove dust; avoid using liquids. If a channel fails, swap sensors between channels to isolate the issue—replace the module if internal faults are confirmed, ensuring the replacement is configured to match the original settings.

Service and guarantee commitment

The AI835A is backed by ABB’s 3-year warranty, covering defects in materials and workmanship under normal operating conditions. During the warranty period, ABB will repair or replace faulty modules at no cost, minimizing downtime in industrial applications.

ABB’s technical support team provides 24/7 assistance for installation, calibration, and troubleshooting, including guidance on integrating the AI835A with the AC800M controller, TB820V2 terminal base, and other related modules. We offer detailed documentation, including wiring diagrams and calibration procedures, to ensure optimal performance.

Extended service contracts are available, offering priority technical support, on-site maintenance, and software updates to keep the AI835A compatible with future system upgrades. ABB’s global service network ensures fast delivery of replacement modules, reducing disruptions in critical processes. Trust the AI835A to deliver reliable, high-density analog data acquisition—backed by ABB’s expertise in industrial automation.