AAI135-H50 | Yokogawa Isolated Current Input Module

Product Overview

The Yokogawa AAI135-H50 serves as a high-performance analog input interface within the CENTUM distributed control system (DCS) architecture. This module processes up to 16 channels of isolated 4 to 20 mA DC signals, converting field data into digital information for the control processor. Even as some older series face manufacturer discontinuation, we provide this unit in 100% brand new, original factory condition to ensure the longevity of your existing control infrastructure.

Technical Specifications

This module provides critical signal isolation to protect the system bus from field-side electrical surges and interference.

Part Number Breakdown: AAI135-H50

Yokogawa part numbers follow a strict functional logic. The AAI135 series is specifically designed for standard current inputs:

• AAI135: Base Model (Isolated Current Input, 4 to 20 mA, 16-channel).

• -H: High-speed / High-reliability industrial specification.

• 5: Standard type (Non-explosion protected).

• 0: Basic connection type (Terminal block or standard interface).

Engineering Advantages

• Signal Isolation Excellence: The 500 V AC withstanding voltage ensures that ground loops or field faults do not damage the expensive central processor units.

• Legacy System Support: As a critical component for many established plants, the AAI135-H50 allows for the maintenance of legacy DCS systems without the need for a full, multi-million dollar system migration.

• Precision Data Acquisition: High-resolution A/D conversion provides the accuracy required for sensitive chemical, oil, and gas process loops.

• Hardened Industrial Build: Designed to operate in high-temperature and high-vibration environments typical of industrial rack rooms, ensuring a long MTBF (Mean Time Between Failure).

FAQs

• Can I use the AAI135-H50 to replace an older AAI135-S series module?

  Yes, the "H" version generally offers superior performance and can replace standard versions, provided the system configuration recognizes the updated hardware ID.

• Is this unit truly brand new if the manufacturer has discontinued the series?

  Yes. We specialize in sourcing "New Old Stock" (NOS) that remains in its original factory-sealed packaging. These units have never been installed or energized.

• What is the primary difference between the AAI135 and the AAI835?

  The AAI135 focuses on standard isolation requirements (500 V AC), whereas the AAI835 typically offers higher isolation ratings (1500 V AC) for more electrically "noisy" environments.

• Does this module support HART communication?

  The AAI135 is a standard analog input module. If your application requires HART protocol pass-through for instrument diagnostics, you may need to consider the AAI143 or AAI841 series.