AAI835-H00 Isolated I/O Module | Yokogawa 4AI/4AO 4-20mA HART

Product Overview

AAI835-H00 is an isolated analog I/O module from Yokogawa. It provides 4 inputs and 4 outputs for 4..20 mA signals. This module offers full channel-to-channel isolation. It supports HART communication and dual-redundant configuration. The module ensures reliable signal integrity in noisy industrial environments.

Key Features

• 4 inputs + 4 outputs (fully isolated channels)
• Signal: 4..20 mA (input and output)
• HART communication available (-H suffix)
• Isolation: 500 V AC between channels and system
• Input accuracy: ±16 µA
• Output accuracy: ±48 µA
• Fast update: 10 ms data refresh

Technical Specifications (Hierarchical)

• General
  • Brand: Yokogawa
  • Model: AAI835-H00
  • Series: AAI835 Analog I/O Module
  • Type: Isolated I/O Module
• I/O Channels
  • Input: 4 channels (4..20 mA)
  • Output: 4 channels (4..20 mA)
  • Isolation: Between all channels and system
• Input Specifications
  • Signal range: 4..20 mA
  • Max input current: 25 mA
  • Input resistance (power ON): 290 Ω at 20 mA, 450 Ω at 4 mA
  • Input resistance (power OFF): ≥500 kΩ
  • Accuracy: ±16 µA
• Output Specifications
  • Signal range: 4..20 mA
  • Load resistance: 0..750 Ω
  • Accuracy: ±48 µA
  • Circuit-open detection: <0.65 mA
• Isolation & Withstanding Voltage
  • I/O to system: 500 V AC (1 minute)
  • Between channels: 500 V AC (1 minute)
• Transmitter Power Supply
  • At 20 mA: ≥15.0 V
  • At 0 mA: ≤29.3 V
• Performance & Environment
  • Data update period: 10 ms
  • Temperature drift: ±16 µA / 10 °C
  • Current consumption: 360 mA (5 V DC), 450 mA (24 V DC)
  • Weight: 0.30 kg
• Connections & Accessories
  • External connection: Pressure clamp, MIL connector, KS1 cable
  • Adapters: ATK4A, ATB3A
  • Terminal boards: AEA4D, AEA3D
  • Redundancy adapters: ATI3S (single), ATI3D (dual redundant)
• Suffix Codes
  • -H: HART protocol
  • 5: No explosion protection
  • 0: Basic type

Expert Review

“AAI835-H00 delivers reliable isolated analog I/O for Yokogawa DCS. The 500 V AC channel isolation protects against ground loops. Its ±16 µA accuracy suits precise process control. We recommend it for critical loops requiring high noise immunity.”

Manager’s Insight

“This module offers excellent isolation for multi-channel analog signals. The compact 4-in/4-out design saves cabinet space. HART communication adds diagnostic value. With 12-month warranty and fast delivery, it is a reliable choice for plant upgrades.”

Applications & Compatible Devices

• Systems: Yokogawa CENTUM VP, ProSafe-RS, STARDOM
• Sensors: 4..20 mA transmitters (pressure, temperature, flow)
• Actuators: I/P converters, control valves, positioners
• Industries: Oil & gas, chemical, power generation, pharmaceuticals
• Use cases: PID control, data acquisition, isolated signal conditioning

Installation & Maintenance

• Mounting: Directly on Yokogawa DCS backplane
• Wiring: Use KS1 cable or pressure clamp terminals
• Redundancy: Dual-redundant with ATI3D adapter
• Terminal boards: AEA4D or AEA3D for easy connection
• Maintenance: Hot-swappable in redundant configurations

Frequently Asked Questions

• Q: What does isolated channels mean?
  Each input and output is electrically isolated from other channels and the system.
• Q: How does -H suffix affect the module?
  -H adds HART communication for digital diagnostics and configuration.
• Q: Can I use this module with 4-wire transmitters?
  Yes. Connect external power separately and use 4-wire mode.
• Q: What is the difference between ATI3S and ATI3D?
  ATI3S is for single configuration; ATI3D is for dual-redundant setup.
• Q: Is the module hot-swappable?
  Yes, in dual-redundant configurations. Power down for single modules.

Experience-based Q&A

• Q: The input reading is noisy. What should I check?
  Verify cable shielding and grounding. Also check for ground loops.
• Q: Can I connect a 2-wire transmitter directly?
  Yes. The module provides loop power for 2-wire transmitters.
• Q: The output does not reach 20 mA. What is wrong?
  Check load resistance (must be ≤750 Ω). Also verify the command signal.

Selection Guide

• For HART communication, choose AAI835-H00 (with -H suffix).
• For non-isolated applications, consider AAI841 (8 in / 8 out, non-isolated).
• For explosion-proof areas, consult safety barrier requirements.
• For redundant systems, use two modules with ATI3D adapter.
• For easy wiring, choose KS1 cable and AEA4D terminal board.

Comparison with Similar Models

• AAI841-H00 – 8 inputs/8 outputs, non-isolated, higher density.
• AAI543-H00 – 4 output channels only.
• AAI141-H00 – 4 input channels only.

Package Contents

• AAI835-H00 analog I/O module (1 unit)
• User manual (English)
• Warranty card (12 months)

Shipping & Delivery

• Dispatch: 12–24 hours after order
• Carriers: FedEx, UPS, DHL (express worldwide)
• Tracking: Provided within 24 hours

Contact Information

For inquiries, contact our sales team:

• Email: sales@powergearx.com
• WhatsApp: +86 18030005825

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