ABB AI845 3BSE023675R1 Analog Input Module

ABB AI845 3BSE023675R1 Analog Input Module

The AI845 Analog Input Module for single or redundant applications. The module has 8 channels. Each channel can be either a voltage or current input when MTU TU844 or TU845 is used, when other MTUs are used all channels become voltage or current inputs.

The voltage and current input is able to withstand an overvoltage or undervoltage of at least 11 V d.c. The input resistance for voltage input is greater than 10 M ohm and the input resistance for current input is 250 ohm.

The module distributes the external HART compatible transmitter supply to each channel. This adds a simple connection to distribute the supply to 2-wire or 3-wire transmitters. The transmitter power is supervised and current limited.

Features and benefits

8 channels for 0...20 mA, 4...20 mA, 0...5 V or 1...5 V d.c., single ended unipolar inputs

Single or redundant operation

1 group of 8 channels isolated from ground

12 Bit resolution

Current limited transmitter supply per channel

Advanced on-board diagnostics

HART pass-through communication

Key technical parameters

Input channel

8 independent analog input channels, supporting inter channel isolation

Support signal types

Thermocouples (K/J/T/E/S, etc.), Thermistors (Pt100/Pt1000/Cu50), 4-20mA DC, 0-10V DC, 0-5V DC

Collection accuracy

± 0.02% FS (standard signal); ±0.1℃（Pt100，0-100℃）； ± 0.2 ℃ (thermocouple, 0-500 ℃)

sampling rate

10Hz-100Hz/channel, software configurable

Isolation performance

Channel isolation: 250V AC; Isolation between channels and systems: 250V AC; Isolation resistance: ≥ 100M Ω

communication interface

Profinet/EtherNet/IP， Communication speed 10/100Mbps adaptive

Cold end compensation

Built in cold end compensation, compensation range -20 ℃~60 ℃, compensation accuracy ± 0.5 ℃

power supply

DC 24V ± 10%, power consumption ≤ 8W

working environment

Temperature: -25 ℃~65 ℃; Humidity: 5%~95% (no condensation); Protection level: IP20 (module body)

Installation method

35mm standard DIN rail installation, supports hot swapping

Overall dimensions

100mm (length) x 80mm (width) x 60mm (height)

Electromagnetic compatibility certification

IEC 61000-4-2 (ESD): ± 8kV contact discharge; IEC 61000-4-3（RS）：10V/m； IEC 61000-4-4（EFT）：±2kV

Applicable scenarios

The AI845 3BSE023675R1 analog input module is widely used in the field of industrial automation due to its high-precision acquisition, multi signal compatibility, and strong anti-interference ability. Typical scenarios include:

1. Chemical process parameter collection: In production equipment such as chemical reaction vessels and distillation towers, modules are used to collect key process parameters such as temperature, pressure, liquid level, and material concentration. By connecting sensors such as thermocouples and pressure transmitters, analog signals are converted into digital signals and uploaded to the DCS system, providing accurate data basis for reaction process control. For example, in the methanol synthesis reaction, the module collects temperature and pressure signals from the reaction kettle to ensure that the reaction proceeds within the set process range and improve product quality.

2. Temperature monitoring in metallurgical industry: In the process of steel and non-ferrous metal smelting, the module is used to collect high temperature parameters such as blast furnace hot blast furnace temperature, converter wall temperature, and continuous casting billet temperature. By connecting high-temperature resistant thermocouples (such as S-type and B-type), the temperature changes in each link of smelting are accurately monitored, providing data support for furnace temperature control and process optimization, ensuring stable smelting process, and reducing energy consumption.

3. Power system operation monitoring: In thermal power plants and substations, modules are used to collect parameters such as turbine generator winding temperature, transformer oil temperature, bus voltage, and current. By connecting Pt100 thermal resistors and power transmitters, the real-time monitoring of the operation status of power equipment is achieved. When the parameters exceed the safe range, timely alarm and protection actions are triggered to ensure the safe operation of the power system.

4. Intelligent manufacturing process detection: In automated production lines and industrial robot workstations, modules are used to collect continuously changing parameters such as conveyor belt speed, material weight, and product size. By connecting to devices such as laser ranging sensors and weighing sensors, analog signals are converted into digital signals, providing accurate data for closed-loop control of production lines and product quality detection, and improving the level of production automation.

5. Water treatment and environmental monitoring: In sewage treatment plants and environmental monitoring stations, modules are used to collect environmental parameters such as sewage pH value, dissolved oxygen content, water turbidity, and atmospheric temperature and humidity. By connecting corresponding analog sensors, the monitoring data is uploaded to the monitoring system, providing reliable basis for environmental standard discharge and environmental quality assessment.

Precautions for use

-Before installing the module, it is necessary to verify that the model, number of channels, and supported signal types match the on-site sensors, and check for any damage to the module's appearance and oxidation of the wiring terminals; The installation location should be selected in a dry and ventilated area, away from high-temperature heat sources (such as heaters and frequency converters), strong electromagnetic interference sources (such as high-power motors), and corrosive gases. The module spacing should be kept at least 5cm to ensure good heat dissipation and avoid direct sunlight.

-Before wiring, it is necessary to disconnect the power supply between the module and the control system, strictly distinguish the wiring terminals of each channel according to the wiring manual, and select the correct wiring method based on the sensor type (such as compensating wires for thermocouples and three wire/four wire wiring for thermal resistors); The analog signal line should be shielded twisted pair and laid separately from the power cable. The shielding layer should be reliably grounded at one end (grounding resistance ≤ 4 Ω) to avoid signal interference.

-Before the module is put into operation, parameter configuration needs to be completed through configuration software, including signal types, sampling rates, filtering parameters, alarm thresholds, etc. After configuration is completed, signal calibration can be performed. Standard signal sources (such as precision signal generators) can be used to calibrate each channel to ensure that the acquisition accuracy meets the requirements; Before hot plugging, it is necessary to perform offline module operations in the control system to avoid module damage caused by live plugging.

-During operation, maintenance personnel need to regularly monitor the module's operating status through LED indicator lights or the upper system, check whether the signals of each channel are normal, check the tightness of the wiring terminals once a week, and clean the dust on the module surface and inside the control cabinet once a month; When a module malfunctions and triggers an alarm, the configuration software can be used to query the fault information and troubleshoot sensor, wiring, or module issues based on the type of fault.

-The recommended module calibration cycle is once a year, and calibration should be carried out by professionals using standard measuring equipment. After calibration, the calibration data and results should be recorded; Firmware upgrade requires obtaining genuine firmware through ABB's official channels. Before upgrading, backup the current configuration parameters. Power interruption is strictly prohibited during the upgrade process. After the upgrade is completed, restart the module and verify that it functions properly.

-When used in high temperature, high humidity, or dusty environments, protective measures such as installing dust-proof and moisture-proof covers should be installed for modules and wiring terminals; In areas with frequent thunderstorms, module power and communication interfaces need to be equipped with lightning surge protectors to prevent module damage caused by lightning strikes; In scenarios with explosion-proof requirements, corresponding explosion-proof modules should be selected and installed according to explosion-proof specifications.