AAI835-S50 | Yokogawa CENTUM VP Analog I/O Module

Product Summary

The Yokogawa AAI835-S50 is a 4-20mA Analog Input/Output Module for the Yokogawa CENTUM VP / CS 3000 distributed control system (DCS). It provides 4 isolated 4-20mA analog input channels and 4 isolated 4-20mA analog output channels in a single module, enabling bidirectional process variable acquisition and control output in compact I/O configurations. The -S50 configuration includes the standard module with the ATK4A-00 KS cable interface adapter for connection to terminal boards via KS cables.

Core Specifications

• Model Number: AAI835-S50
• Type: 4-20mA Analog Input/Output Module (4 Inputs + 4 Outputs, Isolated Channels)
• Input Channels: 4 isolated 4-20mA inputs
• Output Channels: 4 isolated 4-20mA outputs
• Input Signal: 4–20 mA DC
• Output Signal: 4–20 mA DC
• Allowable Input Current: 25 mA maximum
• Allowable Output Load: 0–750 Ω
• Input Accuracy: ±16 µA
• Output Accuracy: ±16 µA
• Resolution: 16-bit (both input and output)
• Data Update Period: 10 ms
• Temperature Drift: ±16 µA/10°C
• Transmitter Power Supply: 15.0 V or higher (at 20 mA); 29.3 V or less (at 0 mA)
• Current Consumption: 360 mA (5 V DC); 450 mA (24 V DC)
• Dimensions (L × W × H): 107 × 130 × 33 mm
• Weight: 0.3 kg
• Manufacturer: Yokogawa Electric Corporation

Electrical & Functional Characteristics

• Signal Isolation: Individual channel isolation prevents ground loops and cross-interference between field devices; isolated between field and system
• Dual-Redundant Configuration: Can be used in dual-redundant I/O configuration for high-availability applications
• Transmitter Power Supply: Built-in 24V loop power supply for 2-wire input transmitters
• Output Protection: Overcurrent and overvoltage protection on each output channel
• Input Protection: Overcurrent protection up to 25 mA per input channel
• Signal Conditioning: Built-in filtering and linearization for stable process variable readings
• Status Indicators: Module status LEDs for power, communication, and channel health
• Hot Swappable: Supports online replacement without system shutdown (when configured)

System Integration & Compatibility

• Primary Platform: Yokogawa CENTUM VP / CS 3000 DCS
• Mounting: FCS (Field Control Station) node unit or I/O expansion rack
• Communication: Vnet/IP or Vnet bus connection to FCS controller
• Configuration: Configured via CENTUM VP Engineering Station (EWS)
• External Connection: ATK4A-00 KS cable interface adapter (included with -S50 suffix); KS cable to terminal board; MIL connector cable; pressure clamp terminal
• Compatible Terminal Boards: AEA8D (for mixed input/output, selectable 2-wire/4-wire)
• Related Modules:
  • AAI835-H00 — HART communication type, non-explosion proof, basic type
  • AAI835-H50 — HART communication type, non-explosion proof, basic type, with ATK4A-00
  • AAI835-S00 — Standard type, non-explosion proof, basic type
  • AAI835-S50 — Standard type, non-explosion proof, basic type, with ATK4A-00 (this part)
  • AAI835-S53 — Standard type, non-explosion proof, with ISA G3 + temperature (-20 to 70°C) option, with ATK4A-00
  • AAI135 — 4-20mA analog input module (8-channel, isolated)
  • AAV144 — 1-5V analog input module (16-channel, non-isolated)
  • AAV542 — 1-5V analog output module (16-channel, non-isolated)

Environmental & Operational Limits

• Operating Temperature: 0°C to 50°C (32°F to 122°F) (basic type); -20°C to 70°C with option code 3
• Storage Temperature: -20°C to +70°C (-4°F to 158°F)
• Humidity: 10% to 90% RH, non-condensing
• Vibration: Compliant with IEC 60068-2-6
• Shock: Compliant with IEC 60068-2-27
• Approvals: CE, UL, CSA (depending on region and certification)

Industrial Applications

Widely deployed in oil & gas refining, petrochemical processing, power generation, water/wastewater treatment, pharmaceutical manufacturing, food & beverage, and pulp & paper industries where compact combined analog input/output with individual channel isolation is required for process control loops, PID control, and cascade control applications.

Frequently Asked Questions

What is the AAI835-S50 used for?

It is a 4-input + 4-output 4-20mA analog I/O module for Yokogawa CENTUM VP / CS 3000 DCS systems, providing bidirectional process variable acquisition and control output with individual channel isolation.

What does the -S50 suffix mean?

-S = Standard type (non-HART); 5 = Non-explosion proof; 0 = Basic type; /K4A00 (implied by -50) = With ATK4A-00 KS cable interface adapter included.

What is the difference between AAI835-S00 and AAI835-S50?

The AAI835-S00 is the basic module without the ATK4A-00 adapter. The AAI835-S50 includes the ATK4A-00 KS cable interface adapter for connection to terminal boards via KS cables.

What is the difference between AAI835-S50 and AAI835-H50?

The AAI835-S50 is the standard type without HART communication. The AAI835-H50 includes HART digital communication capability for smart transmitter configuration and diagnostics on input channels.

Can this module support dual-redundant configuration?

Yes — the AAI835 series supports dual-redundant I/O configuration when paired with dual-redundant terminal boards and appropriate system configuration.

What terminal board do I need?

Use AEA8D terminal board for mixed input/output with selectable 2-wire/4-wire configuration per channel. The KS cable (model KS1) connects the included ATK4A-00 adapter to the terminal board.

What are the related part numbers?

• AAI835-H00 — HART type, non-explosion proof, basic type
• AAI835-H50 — HART type, non-explosion proof, basic type, with ATK4A-00
• AAI835-S00 — Standard type, non-explosion proof, basic type
• AAI835-S50 — Standard type, non-explosion proof, basic type, with ATK4A-00 (this part)
• AAI835-S53 — Standard type, non-explosion proof, G3 + temp option, with ATK4A-00
• AAI135 — 4-20mA analog input module (8-channel, isolated)
• AAV144 — 1-5V analog input module (16-channel, non-isolated)
• ATK4A-00 — KS cable interface adapter (included with -S50)
• AEA8D — Terminal board for mixed analog I/O