Product Overview

The Woodward 1751-147 functions as a high-performance signal conditioning interface for Magnetic Pickup (MPU) sensors. It captures raw, low-voltage pulse signals generated by rotating gear teeth and transforms them into stabilized, clean inputs for turbine governors and engine control processors. By providing a bridge between the harsh electromagnetic environment of the engine and the sensitive logic of the control system, this module ensures accurate frequency and speed monitoring—essential for grid synchronization and overspeed protection.

Condition: 100% Brand New, Original Factory Condition.

Technical Specifications

The 1751-147 utilizes microprocessor-based logic and physical transformer isolation to maintain signal integrity across four independent paths.

Engineering Advantages

• Quad-Channel Redundancy: The 1751-147 provides four separate channels, allowing engineers to connect multiple MPU sensors to a single module. This supports 2-out-of-3 (2oo3) voting architectures or redundant speed sensing loops, preventing a single sensor failure from tripping a turbine.

• Galvanic Transformer Isolation: High-voltage transients and grounding loops frequently plague industrial speed sensing. This module employs physical transformer-based isolation to block electrical noise, ensuring that the control processor receives a "clean" frequency signal regardless of interference on the field wiring.

• Extreme Temperature Resilience: Rated for operation from -40°C to +85°C, the 1751-147 handles the thermal stress of engine-mounted enclosures and remote oil & gas installations. This wide temperature range prevents signal drift that often occurs in lower-grade commercial components.

• Low-Amplitude Signal Sensitivity: The module detects and conditions even low-amplitude pulses at low RPMs. This allows the control system to track turbine speed accurately during start-up and barring cycles before the generator reaches rated frequency.

FAQs

Q: Can I use the 1751-147 with Active (Hall Effect) sensors?

A: No. This module specifically targets Passive Magnetic Pickups (MPU), which generate an AC voltage through induction. Active sensors requiring a power supply typically use different input circuitry.

Q: How does the 1751-147 protect against cable noise?

A: The module utilizes transformer isolation to reject common-mode noise. For optimal results, use twisted-shielded pair cabling for the MPU runs and ensure you ground the shield only at the control cabinet end to prevent ground loops.

Q: Is there a specific mounting orientation required for cooling?

A: While the 1751-147 is ruggedized, we recommend vertical mounting in a ventilated enclosure. The low power consumption of the microprocessor-based design minimizes heat generation, but maintaining airflow around the chassis ensures maximum lifespan in high-ambient environments.

Q: Does the module require manual calibration for different gear tooth counts?

A: The 1751-147 transforms the physical pulse into an electrical signal. You define the tooth-to-RPM conversion logic within the Woodward governor software (like GAP). The module ensures the pulse reaches the software without distortion or loss.