ABB S800 I/O Modules: DLM01,

Technical Dossier

Product Details And Specifications

ABB S800 I/O Series Technical Notes

The Evolution of S800 I/O Architecture

The S800 I/O platform was introduced in the mid-1990s as part of ABB's Master series DCS migration strategy, providing a field-hardened distributed I/O solution compatible with the Advant OCS and later the Industrial IT / System 800xA environments. Early generations used copper-based Modulebus communication; subsequent revisions introduced optical Modulebus (via the DLM01 and DLM02 link modules) to extend station distances and improve noise immunity in high-EMI industrial environments.

The architecture evolved through three distinct phases: (1) Advant-era S800 with copper Modulebus and TB820/TB840 modem boards; (2) Industrial IT-era S800 with optical Modulebus, redundant CI854/CI857 communication interfaces, and expanded I/O density; (3) System 800xA-era S800 with PROFIBUS DP and FOUNDATION Fieldbus gateway integration. As of 2026, the S800 I/O platform is in a mature/end-of-active-development lifecycle. ABB continues to supply spare parts and firmware support, but new installations are directed toward the S900 I/O and ABB Ability™ System 800xA with HART-enabled modules. Long-term maintenance customers relying on S800 infrastructure require access to legacy modules — particularly link modules, power supplies, and analog I/O cards — which are no longer manufactured in volume.

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

Link & Communication Modules

• DLM01: Optical Modulebus link module; connects S800 I/O station to CI8xx controller via fiber optic cable.
• DLM02: Dual optical Modulebus link module; supports redundant optical Modulebus configurations for high-availability stations.
• CI854A: PROFIBUS DP communication interface; connects S800 I/O to PROFIBUS DP master controllers.
• CI857: FOUNDATION Fieldbus HSE communication interface; integrates S800 I/O into FF HSE networks.
• CI858: DeviceNet communication interface for S800 I/O station connectivity.

Analog Input Modules

• AI810: 8-channel analog input module; 4–20 mA / 0–10 V, single-ended, 12-bit resolution.
• AI820: 8-channel analog input module; differential inputs, 13-bit resolution, HART-capable variant available.
• AI830A: 8-channel RTD/thermocouple input module; supports Pt100, Pt1000, J, K, T type sensors.
• AI835A: 8-channel HART-enabled analog input; 4–20 mA with HART pass-through for field device diagnostics.
• AI843: 8-channel high-density analog input; 4–20 mA, 16-bit resolution, suitable for precision measurement loops.

Analog Output Modules

• AO810V2: 8-channel analog output module; 4–20 mA, 12-bit resolution, loop-powered outputs.
• AO820: 8-channel analog output; 0–20 mA / 0–10 V selectable, 13-bit resolution.
• AO835A: 8-channel HART-enabled analog output; 4–20 mA with HART communication for valve positioner integration.

Digital Input Modules

• DI810: 24-channel digital input module; 24 VDC, sink/source configurable, standard process I/O.
• DI820: 24-channel digital input; 120 VAC input capability for direct field wiring without interposing relays.
• DI830: 24-channel digital input; 48 VDC, used in telecom-standard process environments.

Digital Output Modules

• DO810: 24-channel digital output module; 24 VDC, 0.5 A per channel, transistor output.
• DO820: 16-channel relay output module; 250 VAC / 30 VDC, 2 A per channel, for high-current switching applications.

Power Supply & Base Units

• TB820V2: Modulebus modem and power distribution unit; base unit for S800 I/O station assembly.
• TB840A: Redundant Modulebus modem; supports dual-redundant station configurations with automatic switchover.
• SD821: 24 VDC power supply unit; 3 A output, DIN-rail mount, for S800 I/O station power distribution.
• SD822: 24 VDC power supply unit; 5 A output, higher-capacity variant for dense I/O station configurations.