Epro PR9268/20 Electrodynamic Velocity Sensor Probe

Product Overview

The EPRO PR9268/20 is an electrodynamic velocity sensor engineered for continuous vibration measurement of rotating machinery such as turbines, compressors, pumps, and industrial fans. It operates on a self-generating electromagnetic induction principle, delivering a velocity-proportional analog voltage output without external excitation power.

Designed for condition monitoring and protection systems, it is widely used in critical asset health applications where stable long-term signal integrity is required under harsh mechanical and environmental conditions.

Technical Specifications

• Measurement principle: Electrodynamic velocity transducer (magnetic induction)

• Sensitivity: 28.5 mV/mm/s (±5%) at 50 Hz, 20 °C, 100 kΩ load

• Frequency response: 4 Hz to 1000 Hz

• Usable measurement range: up to ±1500 µm displacement / ~100 mm/s velocity

• Natural frequency: 4.5 Hz ±0.75 Hz

• Transverse sensitivity: 0.13 at 110 Hz

• Maximum vibration limit: 3000 µm p-p (mechanical limit 4000 µm p-p)

• Continuous acceleration: 10 g; shock tolerance: 20 g intermittent

• Coil resistance: 1875 Ω ±10%

• Inductance: ≤ 90 mH

• Operating temperature: -20 °C to +100 °C (higher-temp variants available up to +200 °C)

• Protection rating: IP55 standard (IP65 optional configuration)

• Housing material: Aluminum alloy (Al Mg Si Pb F 28)

• Output type: Analog velocity signal (self-powered)

• Connector options: Open cable or C-5015 industrial connector

• Compliance: API 670, ISO 10817-1, DIN 45670

• Weight: 0.8 kg

• Dimensions: approx. 160 × 160 × 120 mm

Key Features

• High sensitivity sensing element for low-amplitude vibration detection

• Stable broadband response suitable for turbomachinery diagnostics

• Self-powered operation eliminating external excitation requirements

• Robust mechanical design for long-term industrial deployment

• IP-rated enclosure for resistance to dust, oil mist, and moisture ingress

• Compatible with major vibration monitoring and protection systems

Installation & Application Notes

The sensor is typically mounted directly on machine bearing housings. For optimal accuracy, vertical installation within ±30° is recommended. Proper cable strain relief and shielding are advised in high-electromagnetic-noise environments. Armored cable options are available for high-vibration or outdoor installations.

Common application areas include steam turbines, gas turbines, centrifugal compressors, pumps, and large industrial ventilation systems.

FAQ

Q: Does the PR9268/20 require external power?
A: No. It is a self-generating velocity sensor and does not require external excitation.

Q: Can it be used for high-temperature machinery?
A: Standard models support up to +100 °C. High-temperature variants extend operation up to +200 °C.

Q: Is it suitable for API 670 systems?
A: Yes, it is designed in compliance with API 670 vibration monitoring requirements.