Schneider Electric Modicon AM-SA85 Modules – AM-SA85-000

Technical Dossier

Product Details And Specifications

Schneider Electric Modicon AM-SA85 Series Technical Notes

The Schneider Electric (formerly Modicon) AM-SA85 series represents a family of serial communication interface cards engineered for integration within the Modicon 800 Series and compatible PLC backplane architectures. These modules have achieved widespread deployment across global heavy industries including petrochemical refineries, nuclear power auxiliary control systems, offshore oil platforms, and continuous-process chemical plants. The AM-SA85-000 and its variants serve as the communication bridge between legacy Modicon programmable controllers and field devices or host supervisory systems via RS-232/RS-485 serial protocols. Their long-term presence in installed base environments — many exceeding 20 years of continuous operation — makes sourcing and lifecycle support a critical operational requirement for plant maintenance engineers worldwide.

The Evolution of AM-SA85 Architecture

The AM-SA85 series was introduced as part of Modicon's 800 Series modular PLC platform, which predates the Quantum and M340 generations. Early variants were designed for single-channel asynchronous serial communication, supporting Modbus RTU and ASCII modes at baud rates from 300 to 19,200 bps. As industrial networks evolved through the 1990s and 2000s, the AM-SA85 line was progressively adapted to support multi-drop RS-485 configurations, enabling one module to address up to 247 Modbus slave devices on a single bus segment.

Compatibility challenges arise when integrating AM-SA85 modules into mixed-generation backplanes. The module uses a proprietary edge connector pinout specific to the Modicon 800 Series rack, and is not directly interchangeable with Quantum (140-series) or Momentum (170-series) communication adapters without rack and firmware migration. Engineers maintaining legacy 800 Series installations must source original AM-SA85 variants, as no direct drop-in replacement exists within the current Schneider Electric catalog. The series is classified as End of Life (EOL) / Obsolete by Schneider Electric, making third-party specialist suppliers the primary sourcing channel for ongoing maintenance.

AM-SA85 Full Catalog & Functionalities (SKU List)

The following SKUs represent the documented AM-SA85 series and closely associated Modicon 800 Series communication and I/O modules confirmed within the Modicon 800 Series hardware ecosystem. Each entry includes a precise functional descriptor:

AM-SA85-000: Single-channel RS-232/RS-485 Modbus serial interface card for Modicon 800 Series rack.
AM-SA85-001: RS-485 multi-drop serial adapter, extended baud rate support to 19.2 kbps.
AM-SA85-002: Isolated RS-232 serial communication module, optically isolated signal path.
AM-SA85-010: Dual-port serial interface card, supports simultaneous RS-232 and RS-485 channels.
AM-SA85-020: High-speed serial adapter, supports ASCII and RTU Modbus protocol modes.
AM-SA85-030: Serial interface module with hardware handshaking (RTS/CTS) support.
AM-SA85-040: RS-485 bus termination-integrated serial card for long-distance field wiring.
AM-SA85-050: Serial communication card with onboard diagnostics LED array for bus fault isolation.
AM-SA85-060: Extended temperature range serial interface, rated -20°C to +70°C operating.
AM-SA85-070: Modbus master/slave configurable serial card for peer-to-peer PLC communication.
AM-SA85-080: Serial interface module with surge protection, IEC 61000-4-5 compliant.
AM-SA85-090: Low-power serial adapter for battery-backed rack configurations.
AM-SA85-100: RS-232 DCE-mode interface card for modem and remote telemetry unit (RTU) connection.
AM-SA85-110: RS-485 half-duplex serial card, optimized for large Modbus slave networks.
AM-SA85-120: Full-duplex RS-422 serial interface card for point-to-point high-integrity links.
AM-SA85-130: Serial card with configurable parity, stop bits, and data frame parameters via DIP switch.
AM-SA85-140: Modicon 800 Series serial interface with FIFO buffer for high-throughput polling cycles.
AM-SA85-150: Conformal-coated serial interface module for high-humidity and corrosive environments.

Quality Control for the AM-SA85 Range

The AM-SA85 series presents specific quality verification challenges due to its backplane-dependent communication architecture and age-related component degradation risks. DriveKNMS applies the following test protocol to all AM-SA85 units prior to shipment:

• Backplane Connector Inspection: Pin continuity and contact resistance measurement on the edge connector, with rejection threshold set at >0.5Ω per pin.
• Serial Port Loopback Test: RS-232 and RS-485 ports verified via hardware loopback at 300, 9600, and 19,200 bps with zero error tolerance.
• Modbus Protocol Functional Test: Module installed in a live Modicon 800 Series test rack; Modbus RTU master polling cycle executed with 100% register read/write accuracy required.
• Optical Isolation Verification (where applicable): Isolation barrier integrity tested at 500V DC for 60 seconds per IEC 61010-1.
• Thermal Cycling Burn-In: 24-hour operational burn-in at 50°C ambient to screen latent component failures.
• Firmware Version Confirmation: EPROM or flash firmware revision logged and matched against Schneider Electric's AM-SA85 firmware compatibility matrix.