Description
Woodward 8562-233
Technical Specifications
- Type: Variable Reluctance (VR) Magnetic Pickup.
- Output: Sine wave AC voltage proportional to speed and air gap.
- Thread Size: Standard 5/8-18 UNF or M16x1.5 (verify specific variant).
- Frequency Range: Wide range covering idle to max overspeed.
Functional Features
- High Sensitivity: Generates sufficient voltage at low cranking speeds for reliable starting.
- Rugged Construction: Hermetically sealed to withstand oil, moisture, and vibration.
- Wide Air Gap: Tolerant to shaft runout and mechanical tolerances.
- EMI Shielding: Integral shielding to prevent false triggering.
Application Scenarios
Mounted on the gearbox or accessory drive of gas turbines, steam turbines, and diesel engines for speed governing and zero-speed detection.
Performance Parameters
- Output Level: Typically >1.5 Vrms at 1000 Hz.
- DC Resistance: Low resistance coil for long cable runs.
Material Composition
Alnico or rare-earth magnet core. Copper wire winding with high-temperature insulation. Stainless steel threaded housing.
Structural Characteristics
Cylindrical probe with a threaded body and a hexagonal head for wrench tightening. Terminates in a shielded two-wire cable or military-style connector.
Working Principle
As gear teeth pass the sensor tip, they disturb the magnetic field, inducing an AC voltage in the coil. The frequency of this voltage is directly proportional to the shaft RPM.
Installation Requirements
Screw into the tapped hole until it contacts the gear, then back off to the specified air gap (typically 0.010″ – 0.030″). Lock with a jam nut. Route cable away from high-voltage VFD cables.
Usage Precautions
- Never use the sensor as a pry bar or hammer it into place.
- Check the gear teeth for damage; missing teeth cause signal dropouts.
- Measure resistance periodically to detect coil degradation.
