ABB TB842 3BSE022464R1 Modules

Technical Dossier

Product Details And Specifications

ABB TB842 Series: Comprehensive Module Range and Technical Overview

The ABB TB842 (3BSE022464R1) is a Termination Unit within ABB's S800 I/O system, designed to interface with the AC800M controller platform. The S800 I/O series holds a dominant installed base across global heavy industry — including petrochemical refineries, nuclear power auxiliary systems, offshore platforms, and large-scale chemical processing plants. The TB842 specifically serves as the termination board for the AI810 and AI820 analog input modules, providing field-side wiring termination with passive signal conditioning. Its modular, DIN-rail-mounted architecture allows hot-swap capability in redundant configurations, making it a critical component in continuous-process environments where unplanned downtime carries significant operational cost.

The Evolution of TB842 Architecture

The S800 I/O system was introduced by ABB in the mid-1990s as the field I/O layer for the Advant OCS and later the AC800M DCS platform. The TB842 termination unit belongs to the first-generation S800 I/O hardware family, which established a standardized backplane bus (ModuleBus) for communication between I/O modules and the controller. Early S800 hardware (circa 1996–2002) used parallel ModuleBus architecture with dedicated termination boards per module type. The TB842 is compatible with AI810 (8-channel, 4–20 mA / 1–5 V) and AI820 (8-channel HART-enabled) analog input modules.

From 2003 onward, ABB introduced the S800 I/O L series with enhanced EMC shielding and extended temperature ratings, while maintaining backward compatibility with existing TB8xx termination units. The TB842 remained unchanged in its electrical interface, ensuring that field wiring installed in the 1990s could be retained during controller upgrades to AC800M v5.x and v6.x firmware generations. As of 2020, the S800 I/O hardware line entered a mature/end-of-active-development phase. ABB continues to supply spare parts and provide lifecycle extension support, but new installations are directed toward the S900 I/O platform. For existing plants, the TB842 remains a long-term maintenance item with a projected support horizon through 2030+ under ABB's Extended Lifecycle Program.

TB842 / S800 I/O Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly stocked modules within the ABB S800 I/O ecosystem. Each is compatible with the AC800M controller family and shares the ModuleBus backplane architecture.

Termination Units (TB8xx Series)

• TB820 / 3BSE013208R1: ModuleBus Modem, single-slot termination for standard I/O modules
• TB840 / 3BSE037760R1: Termination Unit for AI810, passive 8-ch analog input wiring board
• TB842 / 3BSE022464R1: Termination Unit for AI810/AI820, field-side screw terminal block, DIN-rail mount
• TB845 / 3BSE021437R1: Termination Unit for AO810/AO820, 8-ch analog output passive termination
• TB846 / 3BSE022460R1: Termination Unit for DI810/DI811, 16-ch digital input passive wiring board
• TB850 / 3BSE023607R1: Termination Unit for DO810/DO814, 16-ch digital output passive termination
• TB851 / 3BSE023608R1: Termination Unit for DO815, relay output passive termination board
• TB852 / 3BSE018161R1: Termination Unit for DI890/DO890, high-density I/O passive board

Analog Input Modules (AI8xx Series)

• AI810 / 3BSE008516R1: 8-channel analog input, 4–20 mA / 1–5 V, single-ended, S800 ModuleBus
• AI820 / 3BSE008544R1: 8-channel analog input with HART protocol support, 4–20 mA
• AI830 / 3BSE008546R1: 8-channel thermocouple/RTD input, multi-type sensor support
• AI835 / 3BSE008548R1: 8-channel RTD input, Pt100/Pt1000, 3-wire configuration

Analog Output Modules (AO8xx Series)

• AO810 / 3BSE008522R1: 8-channel analog output, 4–20 mA, single-ended, S800 ModuleBus
• AO820 / 3BSE008550R1: 8-channel analog output with HART protocol, 4–20 mA

Digital Input Modules (DI8xx Series)

• DI810 / 3BSE008508R1: 16-channel digital input, 24 VDC, sink/source configurable
• DI811 / 3BSE008510R1: 16-channel digital input, 120 VAC, optically isolated
• DI814 / 3BSE008512R1: 16-channel digital input, 48 VDC, high-density format

Digital Output Modules (DO8xx Series)

• DO810 / 3BSE008514R1: 16-channel digital output, 24 VDC, 0.5 A per channel
• DO814 / 3BSE008518R1: 16-channel digital output, 24 VDC, high-current 2 A per channel
• DO815 / 3BSE013258R1: 8-channel relay output, SPDT, 250 VAC / 5 A rated contacts

Sourcing Hard-to-Find & Obsolete TB842 / S800 I/O Parts

DriveKNMS maintains a dedicated inventory of S800 I/O hardware, including TB842 (3BSE022464R1) units sourced from decommissioned plant assets, authorized surplus channels, and direct OEM stock. For plants operating legacy AC800M or Advant OCS systems, the TB842 is a non-trivial procurement item: ABB's standard distribution channels prioritize active-lifecycle products, and lead times for mature-phase hardware can extend to 16–26 weeks through standard channels.

DriveKNMS provides same-week dispatch for in-stock TB842 units, with full traceability documentation including country of origin (Sweden), manufacturing batch records where available, and pre-shipment test reports. For customers requiring multiple S800 I/O line items — including mixed TB8xx, AI8xx, AO8xx, DI8xx, and DO8xx modules — consolidated BOM sourcing is available with a single point of contact. Obsolete variants with discontinued R-suffix revisions (e.g., R1 vs. R2 hardware revisions) are cross-referenced against known compatibility matrices before dispatch.

Quality Control for the TB842 / S800 I/O Range

Termination units such as the TB842 are passive assemblies; however, failure modes include corroded screw terminals, cracked PCB traces at field-wiring connection points, and degraded backplane connector pins from repeated module insertion cycles. DriveKNMS applies the following inspection protocol to all S800 I/O hardware prior to shipment:

• Visual inspection of all 40-pin backplane connectors under 10× magnification for pin deformation or oxidation
• Continuity verification across all field terminal blocks using calibrated milliohm meter (target: <0.5 Ω per terminal path)
• Insulation resistance test between signal channels and chassis ground (minimum 100 MΩ at 500 VDC)
• Dimensional check of DIN-rail mounting clips for retention force compliance
• Functional loop test with paired AI810 module and AC800M simulator where test bench availability permits

All tested units are labeled with a DriveKNMS QC pass sticker, test date, and technician ID. Test records are retained for 5 years and available on request.