Product Overview

The EPRO PR6424/019-000 16 mm Eddy Current Sensor is a non-contact displacement measurement probe designed for monitoring the operating condition of critical rotating machinery. It belongs to the EPRO PR6424 series, a family of eddy current sensors developed for applications involving steam turbines, gas turbines, hydro turbines, compressors, pumps, fans, and other industrial rotating equipment.

The sensor uses the eddy current measurement principle to detect changes in the distance between its sensing tip and a conductive target, typically a ferromagnetic steel shaft. By measuring these changes without physical contact, the sensor can provide information about shaft displacement, vibration, axial position, eccentricity, and rotational speed-related conditions.

In industrial machinery protection systems, accurate shaft measurement is important for identifying abnormal mechanical behavior. Excessive vibration, shaft movement, changes in operating clearance, and abnormal rotor position can indicate developing equipment problems. A properly installed eddy current sensor helps provide the measurement data required by monitoring and protection equipment.

The PR6424 series features a nominal 16 mm sensing diameter and is designed for dynamic and static displacement measurement. Its published technical characteristics include a sensitivity of 4 V/mm, linearity within ±1.5%, and a static measurement range of ±2.0 mm. The sensor is intended to operate with compatible signal-conditioning equipment that converts the probe response into a usable monitoring signal.

The PR6424/019-000 is identified as a specific model within this sensor family. Because detailed suffix-specific documentation is not readily available, the exact cable length, connector arrangement, and mounting configuration should be checked against the physical product label or manufacturer documentation before ordering.

Technical Specifications

Note: The technical values above describe the PR6424 series. Confirm the exact PR6424/019-000 cable, connector, thread, and temperature configuration before installation or replacement.

Function and Working Principle

The PR6424/019-000 uses eddy current technology to measure the distance between the probe tip and a conductive target. Unlike contact-based measuring devices, the sensor does not need to touch the rotating shaft. This makes it suitable for continuous monitoring of machinery operating at high speeds.

1. Eddy Current Measurement Principle

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

These currents influence the electrical characteristics of the probe coil. The resulting change in the sensor’s electrical response is related to the distance between the sensing tip and the target.

A compatible signal converter processes this response and produces an output proportional to the measured gap. The monitoring system can then use the signal to determine shaft displacement and vibration.

2. Shaft Vibration Measurement

One of the principal applications of the PR6424 series is measuring radial shaft vibration.

As a rotating shaft moves away from or toward the sensor, the distance between the shaft surface and probe changes. The sensor detects this movement and provides a signal representing the displacement.

Monitoring equipment can use the measurement to identify vibration trends, compare operating conditions, and generate alarms when configured limits are exceeded.

3. Axial Position Monitoring

The PR6424 series can also be applied to axial displacement measurement when installed in an appropriate position.

Axial movement monitoring is important for rotating machinery because excessive rotor movement may affect bearing clearances, seals, and other mechanical components.

The probe provides measurement information that can be evaluated by a compatible monitoring system.

4. Eccentricity and Position Measurement

Shaft eccentricity describes the deviation between the shaft’s geometric center and its actual rotational behavior. Excessive eccentricity may contribute to vibration and mechanical instability.

The PR6424 sensor can detect changes in the distance to the shaft surface, supporting the measurement of eccentricity and related position conditions.

5. Speed and Key-Related Measurement

With suitable target geometry and system configuration, eddy current probes can also be used for speed-related measurements.

A monitoring system can detect changes in the probe signal as a shaft feature or target passes the sensor. The resulting signal can support rotational speed or phase-related monitoring functions.

The actual measurement method depends on the installation, target arrangement, converter, and monitoring equipment.

Role in Industrial Machinery Monitoring Systems

The PR6424/019-000 is a sensing component rather than a complete machinery protection system. It normally operates with a compatible signal converter and monitoring equipment.

Probe and Signal Converter

The probe detects the distance to the conductive target and produces an electrical response. A compatible converter processes this response and provides a conditioned output for the monitoring system.

The complete measurement chain must use compatible probe, extension cable, converter, and monitoring hardware. Electrical and mechanical compatibility should be confirmed before combining components from different configurations.

Machinery Protection Systems

The conditioned sensor signal can be connected to machinery monitoring equipment. Depending on the system configuration, the monitoring equipment may evaluate shaft vibration, displacement, position, or other parameters.

When measured values exceed configured limits, the monitoring system can generate alarms or initiate protective actions through the plant control architecture.

DCS and PLC Integration

Machinery monitoring systems may exchange operating information with a distributed control system or programmable logic controller.

For example, a DCS may display vibration trends and equipment status for plant operators, while a dedicated machinery protection system handles the detailed measurement and protection functions.

The PR6424 probe itself does not directly replace a PLC input module or DCS controller. Signal conditioning and compatible monitoring hardware are required.

Industrial Applications

The PR6424 series is designed for demanding rotating machinery applications where non-contact displacement measurement is required.

1. Steam Turbines

Steam turbines operate under high-speed and high-temperature conditions. Monitoring shaft vibration and displacement is important for evaluating rotor behavior and identifying abnormal mechanical conditions.

The PR6424 series can be used as part of a machinery monitoring arrangement to measure shaft movement and provide information for condition assessment.

2. Gas Turbines

Gas turbines contain rotating assemblies that require continuous condition monitoring. Shaft vibration and position measurements help operators evaluate mechanical stability and identify changes in operating behavior.

A properly installed eddy current probe can provide non-contact measurement data for the turbine monitoring system.

3. Hydro Turbines

Hydroelectric generating equipment operates with large rotating assemblies and substantial mechanical loads. Shaft movement and vibration monitoring are important for maintaining stable operation.

The PR6424 series can support radial or axial displacement measurement when selected and installed according to the application requirements.

4. Industrial Compressors

Compressors are widely used in petrochemical plants, refineries, chemical production facilities, and gas-processing installations.

Changes in shaft vibration may indicate mechanical imbalance, bearing problems, misalignment, or other developing equipment conditions. Eddy current probes provide continuous measurement data that can support maintenance and protection strategies.

5. Industrial Pumps

Large process pumps may operate continuously in demanding environments. Shaft displacement and vibration measurements can help maintenance teams identify abnormal operating conditions.

The PR6424 series can be incorporated into suitable pump monitoring systems where non-contact shaft measurement is required.

6. Industrial Fans

Large industrial fans are commonly used in power plants, cement facilities, steel production, and ventilation systems.

Continuous shaft vibration measurement can help identify mechanical changes that may affect equipment reliability. The sensor can provide the measurement signal required by a compatible monitoring arrangement.

Installation and System Integration

Correct installation is essential for accurate measurement and reliable operation. The probe position, target material, cable arrangement, and converter configuration all influence measurement performance.

1. Verify the Sensor Model

Before installation, confirm that the sensor is the correct PR6424 model and that its suffix matches the required cable and connector arrangement.

The PR6424 family includes different cable lengths, mounting arrangements, and configuration options. Do not assume that all PR6424 probes are mechanically interchangeable.

2. Select the Correct Target Surface

The sensor is designed to measure conductive ferromagnetic targets. The published PR6424 specifications identify ferromagnetic steel as the standard target material.

Target material, surface condition, shaft diameter, and installation geometry can affect measurement performance. The target surface should meet the requirements of the selected sensor configuration.

3. Set the Initial Air Gap

The probe must be installed with an appropriate initial gap between its sensing tip and the target surface.

PR6424 series documentation specifies a nominal center air gap of approximately 2.7 mm. The actual installation gap should be established according to the relevant calibration and manufacturer instructions.

Incorrect gap adjustment can reduce measurement accuracy or cause the sensor to operate outside its linear measuring range.

4. Maintain Cable Integrity

The sensor cable should be routed carefully to prevent mechanical damage, excessive bending, and interference from nearby power conductors.

Avoid sharp bends and excessive pulling force. Maintain the minimum bending radius specified for the actual cable configuration.

Cable shielding, connector condition, and grounding should follow the manufacturer’s installation requirements.

5. Connect a Compatible Signal Converter

The PR6424 sensor requires compatible signal-conditioning equipment for a complete measurement system.

The selected converter must match the probe’s electrical characteristics and configuration. Verify the probe model, cable arrangement, converter type, and required output before commissioning.

6. Perform Calibration and Functional Testing

After installation, check the probe gap and verify the measurement signal using the appropriate calibration procedure.

Test the complete signal path from the sensor to the converter and monitoring equipment. Confirm that the output changes correctly when the target distance changes.

Record the initial measurement values and system settings to provide a reference for future maintenance.

Compatible System Components

The PR6424/019-000 should be used with components designed for the corresponding PR6424 measurement configuration.

The listed converters are members of the broader EPRO eddy current measurement ecosystem. Their compatibility with the exact PR6424/019-000 configuration must be confirmed before use.

Alternative Models and Replacement Considerations

The PR6424 family includes different probe configurations. Replacement selection should be based on electrical, mechanical, and installation compatibility rather than the 16 mm sensor diameter alone.

Before replacing the PR6424/019-000, compare:

• Full model and suffix.
• Sensor diameter and mechanical dimensions.
• Thread and mounting arrangement.
• Cable length and cable construction.
• Connector type and pin configuration.
• Compatible signal converter.
• Sensitivity and linear measuring range.
• Target material and shaft geometry.
• Operating temperature requirements.
• Monitoring system input configuration.

A sensor with the same nominal diameter may still have a different electrical or mechanical configuration. Replacement should be approved against the original equipment documentation.

Key Advantages

Non-Contact Measurement

The eddy current principle allows the sensor to measure shaft movement without physical contact. This is suitable for rotating machinery where continuous displacement measurement is required.

High Measurement Sensitivity

The PR6424 series has a published sensitivity of 4 V/mm, supporting the measurement of small changes in target distance when used with compatible signal-conditioning equipment.

Static and Dynamic Measurement

The series supports both static displacement and dynamic shaft movement measurement, allowing it to be used for position and vibration monitoring applications.

Industrial Machinery Applications

The sensor family is designed for use in turbines, compressors, pumps, fans, and other critical rotating machinery.

High-Temperature Capability

PR6424 documentation includes high-temperature operating configurations. The exact operating limit depends on the selected probe and cable arrangement and should be checked before installation.

Integration with Machinery Monitoring Systems

The sensor can be incorporated into a complete machinery monitoring system using compatible converters and monitoring equipment.

Compact 16 mm Sensing Head

The 16 mm probe diameter supports installation in suitable machinery measurement locations where a non-contact sensor is required.

Technical FAQs

1. What is the EPRO PR6424/019-000?

The EPRO PR6424/019-000 is a 16 mm eddy current sensor model in the PR6424 family. It is designed for non-contact measurement of shaft displacement and related mechanical parameters in rotating machinery.

2. What is the sensor head diameter?

The nominal sensing head diameter is 16 mm.

3. What is the measurement principle?

It uses eddy current technology. The probe generates an electromagnetic field, and changes in the distance to a conductive target affect the probe’s electrical response.

4. What is the sensitivity of the PR6424 series?

The published series sensitivity is 4 V/mm. The complete measurement system must use a compatible signal converter.

5. What is the static measurement range?

The PR6424 series has a published static measurement range of ±2.0 mm.

6. What is the dynamic measurement range?

The published dynamic measurement range is 0 to 1,000 μm.

7. What type of target material is required?

The standard target material specified for the series is ferromagnetic steel. Target material and surface characteristics should be checked against the applicable technical documentation.

8. Which signal converter can be used?

Compatible EPRO signal converters include models from the CON011, CON021, CON031, and CON041 families. The correct converter must be selected according to the exact probe and cable configuration.

9. What is the weight of the sensor?

The supplied listing weight is 0.2 kg. PR6424 series documentation also gives a reference weight of approximately 200 grams for the sensor with 1 meter of cable and without armor.

10. Can the PR6424/019-000 directly connect to a PLC?

It should not be treated as a standard direct PLC sensor without checking the interface. A compatible signal converter or machinery monitoring module is normally required to provide a suitable output for the control system.

11. What should be checked before replacing an existing probe?

Confirm the full model number, cable length, connector, mounting thread, converter compatibility, sensitivity, and installation gap. These details are essential for maintaining measurement accuracy.

Procurement and Maintenance Recommendations

When purchasing the EPRO PR6424/019-000, verify the complete model designation and inspect the product label. The PR6424 family contains multiple configurations, and differences in cable length, connector, and mounting arrangement can affect compatibility.

For replacement projects, compare the new probe with the installed unit and confirm that the signal converter supports the selected configuration. Check the sensor head, threaded mounting section, cable insulation, connector, and identification markings.

For used or refurbished products, request clear photographs and confirm the physical condition of the sensing tip and cable. Where possible, obtain functional test information and verify the supplier’s warranty and return conditions.

During routine maintenance, inspect cable routing, connector condition, probe mounting, and the mechanical clearance between the sensor and target. Monitor signal stability and compare operating values with established baseline measurements.

If the measurement becomes unstable, check the initial air gap, cable condition, connector contacts, converter compatibility, target surface, and grounding arrangement. A systematic inspection of the complete measurement chain can help identify the cause of abnormal readings.

Conclusion

The EPRO PR6424/019-000 16 mm Eddy Current Sensor is part of a measurement sensor family designed for non-contact monitoring of critical rotating machinery. Its operating principle supports shaft displacement, vibration, position, eccentricity, and speed-related measurement applications when used with compatible signal-conditioning equipment.

With a nominal 16 mm sensing diameter, 4 V/mm series sensitivity, and a reference weight of approximately 0.2 kg, the PR6424 series is suitable for integration into industrial machinery monitoring systems.

For procurement and replacement, the complete model suffix and associated cable and converter configuration should be verified. Correct installation, calibration, and system compatibility are essential for reliable measurement performance.