AI835A ABB - Thermocouple Module Cold Junction Compensation

ABB AI835/AI835A Thermocouple Input Module (3BSE051306R1)

Advanced 8-channel differential thermocouple and millivolt measurement module featuring configurable cold junction compensation and comprehensive wire-break detection for precision temperature monitoring applications.

Core Capabilities

• Flexible Input Configuration: Supports -30 to +75 mV linear range and multiple thermocouple types including B, C, E, J, K, N, R, S, T (AI835A adds D, L, U)
• Intelligent Cold Junction Compensation: Channel 8 configurable as CJ-channel with 4-wire Pt100 RTD or user-defined fixed temperature
• High Precision Conversion: 15-bit resolution analog-to-digital conversion with >1 MΩ input impedance
• Comprehensive Diagnostics: Continuous monitoring for wire-break open-circuit conditions and temperature limit alerts

Technical Specifications

• Product Identification: 3BSE051306R1 AI835A 
• Measurement Channels: 8 differential inputs
• Signal Ranges: -30 to +75 mV linear, multiple thermocouple types
• Conversion Resolution: 15-bit A/D
• Measurement Accuracy: Maximum 0.1% error
• Sampling Performance: 280-920 ms at 50 Hz, 250-810 ms at 60 Hz
• Noise Immunity: 120 dB CMRR, >60 dB NMRR
• Isolation Rating: 50V group isolation from ground

Cold Junction Compensation

• Flexible CJ Configuration: Channel 8 serves as dedicated cold junction measurement channel
• Multiple Measurement Options: Local MTU terminal sensing, remote connection unit, or fixed parameter value
• Dual-purpose Channel: Channel 8 functions as standard input when CJ compensation not required

Electrical Characteristics

• Power Requirements: 1.6W total (75mA +5V, 50mA +24V Modulebus)
• Input Protection: 500V AC dielectric strength
• Cable Distance: Supports up to 600 meter field wiring
• Temperature Stability: Typical 5 ppm/°C, maximum 7 ppm/°C drift

Application Environments

• High-temperature process monitoring
• Industrial furnace and kiln control
• Precision thermal processing systems
• Multi-zone temperature profiling

Frequently Asked Questions

What thermocouple types are supported?

The module accommodates types B, C, E, J, K, N, R, S, T, with AI835A adding D, L, U compatibility.

How does cold junction compensation work?

Channel 8 can be designated as CJ-channel using 4-wire Pt100 RTD, remote sensing, or fixed temperature parameter.

What diagnostic monitoring is provided?

Continuous wire-break detection, reference channel monitoring, and CJ-temperature range validation.

For pricing and technical support, please contact: sale@etowonauto.com