Description

Woodward PXAH411 High Density Analog Input Processing Module

Technical Specifications

• Product Model: PXAH411
• Brand: Woodward
• Warranty: One Year
• Input Voltage: 24 VDC ±10% backplane rack power supply
• Operating Temperature: 0°C to +60°C
• Storage Temperature: -40°C to +85°C
• Response Time: ≤1.5ms per channel analog sampling and A/D conversion
• Protection Class: IP20 rack-mounted installation in control cabinet
• Accuracy Class: ±0.05% full scale analog conversion precision with channel isolation
• Output Frequency: Internal sampling clock 8kHz continuous scanning
• Rated Current Range: Maximum 1.2A total module power consumption at 24VDC
• Communication Interface: Proprietary Woodward MicroNet TMR backplane bus, field terminal block wiring
• Supported Protocols: MicroNet internal redundant control bus, analog 4–20mA, 0–10VDC standard industrial signals
• Overload Capacity: Per-channel overvoltage clamping, reverse wiring protection, EMC surge and transient suppression
• Dimensions: 233mm (L) × 128mm (W) × 32mm (H), standard Woodward 6U rack form factor
• 

Product Overview

The PXAH411 is a high-density redundant analog input acquisition module designed exclusively for Woodward MicroNet TMR turbine and reciprocating engine control safety systems. This rack-based I/O board serves as the primary signal conditioning front end for critical process parameters in gas turbines, steam turbines, diesel generator sets and combined-cycle power plants, converting raw field transmitter analog signals into digital data for the main TMR voting controller to execute speed regulation, load control and machinery protection trip logic.

It resolves critical reliability challenges in power generation safety control systems, including inaccurate multi-channel analog sampling leading to false equipment trips, lack of galvanic isolation causing cross-channel signal crosstalk, insufficient fault diagnosis for open/short transmitter loops, and complicated spare module replacement within triple modular redundant architectures. Built with isolated per-channel circuits, on-board signal filtering, hardware voting matching and comprehensive self-test diagnostics, the module maintains stable measurement performance under high cabinet ambient temperature, severe generator room vibration and grid electrical harmonic interference.

Power plant control instrumentation engineers, turbine protection system maintenance technicians, Woodward TMR system integrators and power asset reliability teams gain direct operational value from this OEM spare component. It supports hot-swappable rack replacement during scheduled outages without shutting down the host control system, automatically validates channel integrity and flags faulty field wiring, preserves the original system safety voting logic after replacement, and minimizes forced outage risks caused by degraded analog signal acquisition in critical prime mover control loops.