AAI135-S50 | Yokogawa CENTUM VP 8-Channel Isolated Analog Input Module

Product Description

The AAI135-S50 (Part Number AAI135-S50) is a high-performance current input interface engineered for the Yokogawa CENTUM VP and CS 3000 distributed control systems. This module is designed to capture 4 to 20 mA DC signals from field transmitters with an emphasis on signal integrity. Featuring eight fully isolated channels, the AAI135-S50 effectively prevents ground loops and eliminates common-mode noise, making it an essential component for environments where electrical interference could compromise process data.

As a standard functional type, the AAI135-S50 is built for safe-area installations. It offers multiple physical interface options, including direct pressure clamp terminals, high-density MIL connector cables, or the proprietary KS1 signal cable system. This flexibility allows engineers to integrate the module into various cabinet architectures while maintaining a compact footprint and high reliability.

Detailed Technical Specifications

• Input Channels 8 channels, individually isolated

• Input Signal Range 4 to 20 mA DC

• Module Accuracy ±16 μA (±0.1% of span)

• Data Update Cycle 40 ms

• Input Impedance 250 Ω (during power-on)

• Dielectric Withstand Voltage 1500 V AC between input signals and system for 1 minute

• Current Consumption 360 mA maximum at 5 V DC; 450 mA maximum at 24 V DC

• Mounting Configuration Dual-redundant compatible

• Operating Temperature -20 to 70°C (standard range)

• Dimensions 10.7 cm x 13.0 cm x 3.3 cm

• Weight 0.3 kg

Model Suffix Definitions

• AAI135 Base series for 8-channel isolated current input

• -S Standard communication and performance type

• 5 Non-explosion protected hardware for safe zone use

• 0 Basic functional hardware configuration

Industrial Applications

• Refining and Petrochemical monitoring where channel isolation is critical for safety-instrumented functions.

• Power plant boiler control systems requiring stable 4-20 mA data acquisition.

• Remote I/O nests in water treatment facilities where ground potential differences are common.

• Process automation loops requiring high-density, isolated analog sensing.

Technical FAQ

Why should I choose the AAI135 over a non-isolated module?The AAI135-S50 provides 1.5 kV galvanic isolation between channels and the system. This protection is vital in large plants where field sensors may have different ground potentials, preventing signal distortion and hardware damage from electrical surges.

Is this module compatible with existing KS1 cables?Yes, the AAI135-S50 supports the dedicated KS1 cable interface. This allows for a plug-and-play connection to Yokogawa terminal boards, significantly reducing manual wiring time and potential errors during site commissioning.