Description

ABB AI893 3BSC690141R1

ABB AI893 3BSC690141R1 is an analog input module, whose core positioning is to achieve the accurate acquisition and transmission of thermocouple (TC) and millivolt (mV) signals in industrial hazardous environments. It undertakes the core task of converting analog signals generated by converting on-site physical quantities such as temperature into digital signals recognizable by the control system, and ensuring the safety and reliability of signal acquisition in hazardous areas through intrinsically safe design. It is a key interface component connecting sensors under hazardous working conditions and upper control systems (such as the 800xA system). This module is widely used in hazardous industrial scenarios with flammable and explosive media such as petrochemicals, mining, and pharmaceutical chemicals, as well as in fields with stringent requirements for signal acquisition accuracy and safety such as conventional industrial automation, process control, and environmental monitoring. It can be accurately matched with relevant control systems of the S800 I/O series, providing reliable data support for automated precision control in hazardous environments.

Relying on intrinsically safe circuit design, multi-type thermocouple adaptation capability, and full-channel differential input design, the ABB AI893 3BSC690141R1 module can stably acquire weak analog signals in hazardous environments, effectively avoiding potential safety risks during the acquisition process. At the same time, it improves the anti-interference capability and accuracy of signal acquisition, reduces system downtime caused by environmental interference or safety hazards, and lowers operation and maintenance costs. It is a key core component in the automated monitoring loop of hazardous industrial scenarios.

1. Product Features

1.1 Intrinsically Safe Design for Hazardous Environments

Adopting intrinsically safe circuit design, it can be directly applied to hazardous industrial scenarios with flammable and explosive media without the need for additional safety isolation devices, avoiding potential safety risks during signal acquisition from the source. It must be used with dedicated TU890 or TU891 terminal units to further ensure loop safety and signal transmission stability, complying with relevant safety specifications for industrial hazardous environments.

1.2 8-Channel Differential Input for Multi-Type Thermocouples

Equipped with 8 differential input channels, it is specially designed for thermocouple/mV signal measurement. It supports a wide range of thermocouple types including B, C, E, J, K, L, N, R, S, T, and U. The measurement range of each channel can be configured as a linear range of -30mV to 75mV, or matched with the temperature measurement range of the corresponding thermocouple type, enabling accurate capture of subtle changes in weak analog signals on site.

1.3 Built-in Cold-Junction Compensation for Excellent Acquisition Accuracy

Channel 8 of the module can be flexibly configured as a "cold-junction (ambient) temperature measurement" channel, serving as the cold-junction compensation reference for other thermocouple channels. It eliminates the need for additional cold-junction compensation modules, simplifying system design while improving temperature measurement accuracy. It adopts a high-precision signal acquisition circuit, which can effectively reduce the impact of ambient temperature fluctuations on measurement results and ensure the accuracy of collected data under complex working conditions.

1.4 Comprehensive Fault Monitoring for Easy Operation and Maintenance

It is equipped with input open-circuit monitoring function, which can monitor the line connection status of each input channel in real time. When faults such as sensor disconnection and line open circuit are detected, it immediately generates a fault signal and feeds it back to the upper control system, and intuitively displays the fault status through local status indicators. It helps operation and maintenance personnel quickly locate fault points, greatly shortening fault troubleshooting time and improving operation and maintenance efficiency.

1.5 Modular Design for Flexible Integration and Adaptation

Adopting the standard modular package design of the ABB S800 I/O series, it features convenient installation and can be easily integrated into industrial standard control cabinets and related control systems. It supports compatibility and adaptation with I/O modules of multiple versions (4.0, 4.1, 5.0, 5.1, 6.0, etc.) of the 800xA system, with good system scalability, simplifying the system construction and upgrade process.

1.6 Wide Working Condition Adaptation for Strong Environmental Suitability

Using industrial-grade high-quality components, it can adapt to the complex temperature and humidity environment of industrial sites, with good anti-electromagnetic interference capability and mechanical stability. It can operate stably for a long time within the conventional industrial temperature and humidity range. Meanwhile, through intrinsically safe design, it can withstand special working conditions in hazardous environments, ensuring the operational reliability and service life of the module.

2. Technical Parameters

2.1 Basic Parameters

Model: ABB AI893 3BSC690141R1
Product Type: Intrinsically Safe Analog Input Module
Brand: ABB
Product Series: System 800xA Series, S800 I/O Module Series
Application Fields: Hazardous industrial scenarios such as petrochemicals, mining, pharmaceutical chemicals; industrial automation, process control, environmental monitoring
Compatible Systems: ABB 800xA System (Versions 4.0/4.1/5.0/5.1/6.0, etc.), S800 I/O Series Control Systems
Number of Input Channels: 8 channels (differential input)
Compatible Signal Types: Multiple thermocouples (Types B, C, E, J, K, L, N, R, S, T, U), mV signals
Dedicated Terminal Unit: Must be used with TU890 or TU891
Mounting Method: Standard Modular Mounting
Net Weight: Approximately 0.3kg
RoHS Compliance: Complies with EU Directive 2011/65/EU
WEEE Category: Category 5 (small equipment with external dimensions not exceeding 50 cm in all aspects)
HS Code: 85389099

2.2 Electrical Parameters

Measurement Range: -30mV~75mV (linear) or temperature range corresponding to thermocouple type
Input Type: Differential Input
Channel Configuration: Channel 8 can be configured as cold-junction temperature measurement channel
Fault Monitoring: Supports input open-circuit monitoring
Communication Interface: Compatible with S800 I/O system bus protocol
Power Supply Method: Powered via backplane bus or dedicated terminal unit (meeting intrinsically safe power supply requirements)

2.3 Mechanical and Environmental Parameters

Dimensions (W×H×D): 45mm×119mm×102mm
Operating Temperature: Conventional industrial temperature and humidity range (adapted to normal working conditions in hazardous environments)
Storage Temperature: -40℃~+85℃
Relative Humidity: 5%~95%RH (no condensation)
Electromagnetic Interference Resistance: Complies with relevant industrial-grade anti-interference standards
Protection Rating: IP20 (front-end protection after installation)
Housing Material: Flame-retardant engineering plastic + metal shielding cover

3. Working Principle

The core working logic of the ABB AI893 3BSC690141R1 intrinsically safe analog input module is "Intrinsically Safe Power Supply - Signal Acquisition and Adaptation - Cold-Junction Compensation - Signal Conditioning - A/D Conversion - Digital Transmission - Fault Monitoring and Feedback". The specific working process is as follows:

Intrinsically Safe Power Supply and Initialization: The module obtains working power meeting intrinsically safe requirements through the backplane bus or the matched TU890/TU891 terminal unit. The built-in stable power supply circuit provides safe and stable power for internal acquisition circuits, communication circuits, etc. After power-on, the module automatically completes initialization, detects the status of internal circuits, channel configuration parameters, and the communication link with the upper system, preparing for signal acquisition.

Signal Acquisition and Adaptation: On-site industrial thermocouple sensors convert physical quantities such as temperature into mV-level analog signals, which are transmitted to the corresponding differential input channels of the module through dedicated intrinsically safe cables. According to the preset channel configuration parameters, the module automatically adapts to the corresponding thermocouple type or mV signal range, realizing accurate adaptive acquisition of different types of input signals.

Cold-Junction Compensation and Signal Conditioning: If the cold-junction compensation function is enabled in the system, the module collects the ambient temperature signal through channel 8 configured for cold-junction measurement, and uses this as a reference to perform cold-junction compensation correction on the collected signals of other thermocouple channels. Meanwhile, the collected analog signals are amplified and denoised by the internal conditioning circuit to remove noise components such as electromagnetic interference in the industrial field, improving signal stability.

A/D Conversion and Digital Transmission: The conditioned analog signals are sent to the high-precision A/D conversion chip to be converted into digital signals. The built-in microprocessor verifies and converts the format of the digital signals, and then transmits them to the upper control system (such as the 800xA system) through the system bus, realizing the digital acquisition and upload of analog signals in hazardous environments.

Fault Monitoring and Feedback: The module monitors the line connection status, signal amplitude of each input channel and its own working status in real time. When detecting channel open-circuit, signal abnormality or internal faults, it immediately generates fault information including fault type and fault channel, feeds it back to the upper control system through the bus, and triggers the local status indicator to alarm, reminding operation and maintenance personnel to handle it in a timely manner while ensuring the safety of the intrinsically safe loop.

4. Common Fault Troubleshooting

Fault Phenomenon	Possible Causes	Troubleshooting and Solutions
No response when the module is powered on, and the status indicator light does not turn on	Abnormal intrinsically safe power supply, loose backplane bus connection, TU890/TU891 terminal unit failure, damaged power connection cable, internal power circuit failure of the module	Check whether the output of the intrinsically safe power supply meets the requirements to ensure the power supply is normal; check whether the connection between the module and the backplane bus, terminal unit is firm, re-plug and tighten; troubleshoot the working status of the TU890/TU891 terminal unit to confirm it is fault-free; check whether the power connection cable is damaged and replace it with a qualified cable; if the above inspections are normal but there is still no response, contact ABB authorized after-sales service for maintenance or module replacement.
Large temperature measurement deviation of a certain channel	Channel configuration error (mismatched thermocouple type), cold-junction compensation channel not enabled or faulty, incorrect sensor wiring (reversed positive and negative poles), sensor failure, signal cable interference	Check the channel configuration through the control system software to confirm that the thermocouple type matches the actual sensor, reconfigure and save; check whether channel 8 has enabled the cold-junction compensation function, enable it if not, and test whether the acquisition of channel 8 is normal if it has been enabled; verify the sensor wiring to ensure correct connection of positive and negative poles; disconnect the connection between the sensor and the module, connect a standard signal source to the channel for testing, replace the sensor if the data is normal; check whether the signal cable is a shielded cable and whether the shielding layer is grounded, replace the shielded cable and ensure reliable grounding to reduce interference.
The module frequently triggers channel open-circuit alarms	Sensor disconnection, damaged signal cable, loose channel wiring, oxidized wiring terminals, internal channel circuit failure of the module	Check whether the sensor connection of the corresponding channel is normal, troubleshoot whether the sensor is disconnected, replace the faulty sensor; check whether the signal cable is damaged or broken, replace it with an intact cable; check whether the channel wiring is loose and re-tighten the wiring; check whether the wiring terminals are oxidized, clean the oxide layer or replace the terminals; if the above measures are ineffective, there may be a fault in the internal channel circuit of the module, contact after-sales service for maintenance or module replacement.
Communication abnormality between the module and the control system	Loose backplane bus connection, incorrect module address configuration, mismatched communication protocol, outdated module firmware version, control system interface failure	Re-plug the module to ensure firm connection with the backplane bus; check the module address configuration to ensure it is consistent with the address allocation of the control system; confirm that the communication protocol configuration is correct and compatible with the 800xA system; check the module firmware version, contact ABB authorized after-sales service for firmware upgrade if the version is outdated; if other modules communicate normally, there may be a fault in the module communication interface, contact after-sales service for maintenance or module replacement.
Large fluctuation of signals collected by all channels	Excessive electromagnetic interference on site, unshielded or poorly shielded signal cables, poor module grounding, non-standard wiring of intrinsically safe loops	Check whether the module installation location is close to strong interference sources, install a metal shielding cover or optimize the installation location; ensure that the signal cable is a qualified shielded cable with the shielding layer reliably grounded at one end; check whether the module grounding is good and re-tighten the grounding terminal; verify whether the wiring of the intrinsically safe loop complies with specifications, avoid parallel wiring with power cables, and rectify non-standard wiring.