Product Overview

The EPRO PR6424/013-130 16 mm Eddy Current Sensor is a non-contact displacement sensor designed for monitoring the condition and operating behavior of rotating machinery. It belongs to the EPRO PR6424 sensor family and is used in industrial equipment where accurate shaft displacement, vibration, position, and eccentricity measurements are important for reliable operation.

The sensor operates using the eddy current measurement principle. Instead of making physical contact with the rotating shaft, it generates an electromagnetic field and detects changes in that field caused by the distance between the sensor tip and a conductive target. This allows it to monitor shaft movement without introducing mechanical contact or additional friction.

The PR6424 series is commonly used in critical turbomachinery applications, including steam turbines, gas turbines, hydraulic turbines, compressors, pumps, and industrial fans. These machines often operate under high speeds, changing loads, and demanding environmental conditions. Continuous shaft monitoring helps operators identify abnormal vibration and displacement before equipment problems develop into serious failures.

The PR6424/013-130 features a 16 mm sensor head and is intended to operate as part of a compatible EPRO eddy current measurement system. The complete measuring arrangement normally includes the sensor, an appropriate extension cable, and a compatible signal converter.

For industrial maintenance and replacement projects, verifying the complete model number and matching converter and cable configuration is essential.

Technical Specifications

Note: The specifications above describe the PR6424 sensor family. Exact cable length, connector arrangement, installation dimensions, and environmental limits should be confirmed against the documentation supplied with the specific PR6424/013-130 unit.

Function and Working Principle

The PR6424/013-130 uses eddy current technology to measure the distance between its sensing tip and a conductive metallic target. This measurement principle is particularly useful for monitoring the movement of rotating shafts in industrial machinery.

1. Non-Contact Displacement Measurement

The sensor generates an electromagnetic field around its sensing tip. When a conductive metallic target approaches the sensor, eddy currents are induced in the target surface.

The resulting change in the electromagnetic field affects the sensor’s electrical characteristics. A compatible signal converter processes this response and produces a measurement signal corresponding to the distance between the sensor and the target.

Because the sensor does not touch the shaft, it can continuously measure movement without mechanical wear caused by contact.

2. Shaft Vibration Monitoring

Rotating machinery may experience vibration due to imbalance, misalignment, bearing deterioration, looseness, or changing operating conditions.

The PR6424 sensor can detect dynamic changes in the distance between the shaft surface and the sensor tip. These measurements provide information about shaft vibration and movement.

When connected to a suitable monitoring system, the measurement data can be used to evaluate machinery condition and identify abnormal operating patterns.

3. Shaft Position Measurement

In addition to dynamic vibration, the sensor can measure static shaft displacement within its specified linear range.

This capability is useful for monitoring shaft position in machines with sleeve bearings, where direct measurement of shaft movement provides information that may not be visible through conventional casing-mounted vibration sensors.

4. Eccentricity and Axial Displacement Monitoring

The PR6424 family can be used in applications requiring eccentricity and axial or radial shaft displacement measurements.

Eccentricity monitoring helps identify uneven shaft rotation or geometric irregularities. Axial displacement monitoring can provide information about changes in shaft position along the machine’s rotational axis.

The measurement arrangement must be designed with the appropriate sensor orientation, target surface, and converter configuration.

Role in Industrial Machinery Protection Systems

The PR6424/013-130 is designed to operate as a sensing component within a broader machinery monitoring and protection system.

It does not independently provide a complete machine protection function. Instead, it supplies measurement information to compatible signal-conditioning and monitoring equipment.

1. Integration with EPRO Signal Converters

The sensor normally works with a compatible EPRO signal converter. The converter supplies the required excitation and processes the sensor response into a usable measurement signal.

The converter must match the sensor’s electrical characteristics, cable arrangement, and measurement configuration.

Incorrect combinations may result in inaccurate measurements or an inability to obtain a valid signal.

2. Integration with Machinery Monitoring Systems

The processed sensor signal can be connected to an appropriate machinery monitoring platform.

Depending on the monitoring system, the measurement may be used for:

• Shaft vibration monitoring.
• Radial shaft displacement.
• Axial shaft position.
• Eccentricity measurement.
• Rotating machinery condition analysis.
• Alarm and trip monitoring.

3. Integration with DCS and PLC Systems

In industrial installations, machinery monitoring equipment may communicate operating information to a distributed control system or programmable logic controller.

This allows operators to view machinery condition information alongside other process variables, such as pressure, temperature, flow, and motor operating status.

The actual interface depends on the monitoring equipment and system architecture. The PR6424 sensor itself should not be treated as a direct PLC or DCS communication module.

Industrial Applications

1. Steam Turbines

Steam turbines operate under high-speed and demanding mechanical conditions. Continuous shaft displacement and vibration monitoring are important for evaluating rotor behavior and detecting abnormal movement.

The PR6424 sensor can be installed at appropriate measurement locations to monitor radial shaft movement and other relevant displacement parameters.

2. Gas Turbines

Gas turbines are used in power generation and industrial applications where equipment reliability is essential.

Non-contact shaft sensors provide measurement information that can help monitoring systems identify changes in rotor vibration and position.

The PR6424 series is suitable for relevant turbomachinery monitoring applications when the sensor configuration meets the installation requirements.

3. Industrial Compressors

Compressors are widely used in petrochemical plants, natural gas facilities, refineries, and manufacturing operations.

Shaft vibration and displacement monitoring can help maintenance teams identify developing mechanical problems, including imbalance, misalignment, and bearing-related issues.

4. Pumps

Large industrial pumps may operate continuously under varying process loads. Shaft movement monitoring provides useful information about mechanical operating conditions.

The PR6424 sensor can be used in compatible pump installations where non-contact shaft measurement is required.

5. Industrial Fans and Blowers

Large fans and blowers are common in power plants, chemical facilities, and industrial ventilation systems.

Monitoring shaft movement and vibration can help identify mechanical changes that may affect equipment reliability and operating stability.

Installation and System Integration

Correct installation is essential for obtaining reliable measurements from the PR6424/013-130.

1. Sensor Mounting

The sensor should be installed at the specified measurement location using a suitable mounting arrangement.

The sensing tip must face the target surface with the required alignment and clearance. The mounting structure should be sufficiently rigid to prevent unwanted sensor movement during machine operation.

2. Air Gap Adjustment

The distance between the sensor tip and the shaft surface is an important installation parameter.

The PR6424 series has a nominal center air gap of approximately 2.7 mm. The final installation position should be adjusted according to the applicable sensor and converter specifications.

Incorrect air gap adjustment may result in measurement errors or operation outside the sensor’s linear measuring range.

3. Target Surface Requirements

Eddy current sensors require an appropriate conductive target material.

The PR6424 specifications identify ferromagnetic steel as the standard target material. Surface condition, material composition, shaft diameter, and target geometry should be considered during installation.

4. Cable Routing

The sensor cable should be routed carefully to avoid excessive bending, mechanical damage, and interference from high-power electrical equipment.

Where shielding and grounding are required, follow the manufacturer’s wiring instructions.

Cable length and connector configuration must be compatible with the signal converter. Avoid making unapproved cable substitutions.

5. Converter Configuration

Connect the sensor to the appropriate EPRO signal converter and verify the complete measurement chain.

Check the sensor identification, cable arrangement, converter settings, output signal, and measurement calibration before placing the equipment into service.

6. Commissioning and Functional Testing

After installation, verify the sensor’s mechanical position and electrical connections.

The commissioning procedure should include checking the initial air gap, confirming the converter output, comparing the measurement with expected shaft conditions, and verifying the monitoring system’s alarm settings.

Compatible System Components

The PR6424/013-130 is normally part of a complete eddy current measurement system.

The sensor, extension cable, converter, and monitoring module should be treated as a matched measurement chain. Confirm the exact compatibility requirements before replacing individual components.

Alternative Models and Replacement Considerations

The EPRO PR6424 belongs to a broader family of eddy current displacement sensors. Other models may have different sensor diameters, measuring ranges, mounting arrangements, and environmental capabilities.

Before selecting an alternative, verify:

• Sensor head diameter.
• Complete model and ordering code.
• Measurement range and sensitivity.
• Nominal air gap.
• Target material and shaft diameter.
• Sensor mounting thread.
• Cable length and connector type.
• Signal converter compatibility.
• Operating temperature requirements.
• Monitoring-system input configuration.

A sensor with the same nominal diameter is not necessarily a direct replacement. Electrical characteristics and the complete measurement-chain configuration must also match.

Key Advantages

Non-Contact Measurement

The sensor measures shaft movement without physical contact, avoiding mechanical contact wear during normal operation.

Accurate Displacement Monitoring

The PR6424 series provides a defined sensitivity and linear measurement range for suitable shaft monitoring applications.

Suitable for Critical Rotating Machinery

Its application range includes turbines, compressors, pumps, and fans used in demanding industrial environments.

Static and Dynamic Measurement

The sensor family supports both static shaft position measurement and dynamic displacement monitoring within the specified operating range.

Stainless Steel Construction

The sensor sleeve uses stainless steel, providing a robust mechanical construction for industrial installation.

Integration with Machinery Monitoring Systems

When paired with a compatible converter, the sensor can provide measurement signals for machinery condition monitoring and protection systems.

Technical FAQs

1. What is the EPRO PR6424/013-130?

The PR6424/013-130 is a 16 mm eddy current sensor designed for non-contact measurement of shaft displacement and movement in rotating machinery.

2. What is the sensor head diameter?

The sensor head diameter is 16 mm.

3. What is the working principle of the PR6424 sensor?

It uses electromagnetic eddy current technology. Changes in the distance between the sensor and a conductive metallic target affect the electromagnetic response, allowing the system to measure displacement.

4. What is the typical sensitivity of the PR6424 series?

The published PR6424 series sensitivity is 4 V/mm, with a linearity specification of no more than ±1.5%.

5. What is the static measurement range?

The published static measurement range is ±2.0 mm. The actual usable range depends on the sensor and converter configuration.

6. What machines can use this sensor?

Typical applications include steam turbines, gas turbines, hydraulic turbines, compressors, pumps, and industrial fans.

7. Does the sensor need a signal converter?

Yes. The sensor normally operates as part of a complete measurement system with a compatible signal converter and cable arrangement.

8. Can the PR6424/013-130 measure shaft vibration?

Yes. Dynamic changes in the distance between the sensor tip and shaft surface can be used to monitor shaft vibration when connected to a suitable measurement and monitoring system.

9. What is the weight of the sensor?

The supplied product weight is 0.2 kg. The PR6424 specification sheet also gives an approximate weight of 200 grams for the sensor with a 1-meter cable, excluding armor.

10. What should be checked before purchasing a replacement?

Verify the complete model number, sensor diameter, measurement range, cable length, connector arrangement, signal converter compatibility, and physical condition.

Procurement and Maintenance Recommendations

When purchasing the EPRO PR6424/013-130, verify the complete product code rather than relying only on the PR6424 series designation. Different suffixes may identify different sensor configurations.

For replacement projects, compare the original sensor with the proposed replacement and confirm that the converter, extension cable, and monitoring system are compatible.

For used or surplus sensors, inspect the sensing tip, threaded sleeve, cable, connector, and identification label. Request photographs and functional test information where available.

During maintenance, inspect the sensor mounting arrangement and cable condition. Check for loose mounting hardware, damaged insulation, connector contamination, and changes in the sensor’s measurement output.

A stable installation and correctly configured measurement chain are important for obtaining reliable machinery monitoring data.

Conclusion

The EPRO PR6424/013-130 16 mm Eddy Current Sensor is designed for non-contact shaft displacement and vibration monitoring in critical rotating machinery. Its 16 mm sensor head and eddy current measurement principle make it suitable for applications involving turbines, compressors, pumps, and industrial fans.

With a typical PR6424 series sensitivity of 4 V/mm and a static measurement range of ±2.0 mm, the sensor can provide useful shaft position and movement information when paired with a compatible signal converter and monitoring system.

For industrial maintenance, spare-parts procurement, and machinery protection applications, confirming the complete model number and measurement-system compatibility is essential for reliable replacement and long-term operation.