Description
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Emerson EPRO |
| Model | PR6423/003-030-CN |
| Sensor Type | Eddy-current displacement sensor |
| Probe Tip Diameter | 8 mm |
| Measuring Principle | Non-contact eddy-current |
| Linear Measurement Range | 2 mm / 80 mils |
| Initial Air Gap | 0.5 mm / 20 mils |
| Incremental Scale Factor | 8 V/mm / 203.2 mV/mil ±5% |
| Linearity Deviation | ±0.025 mm / ±1 mil |
| Minimum Shaft Diameter | 25 mm / 0.79 in |
| Standard Target Material | Ferromagnetic steel, 42CrMo4 / AISI 4140 |
| Sensor Protection | IP66 |
| Sensor Temperature | -35°C to +180°C for current PR6423 specification |
| Cable & Connector Temperature | -35°C to +150°C |
| Case Thread | M10 × 1 or 3/8-24 UNF, depending configuration |
| Typical Converter | CON021 |
| Typical System | EPRO machinery monitoring / protection systems |
The current Emerson specification gives the PR6423 a 2 mm linear measurement range, 0.5 mm initial air gap, 8 V/mm sensitivity, IP66 protection, and a minimum shaft diameter of 25 mm. It also identifies the sensor for radial and axial shaft dynamic displacement, position, eccentricity, and speed measurement.
The /003-030 configuration is commonly documented with an M10 × 1 mounting arrangement, 55 mm sleeve, and approximately 8 m cable with LEMO termination. Because configuration-code interpretations vary across secondary documentation, the physical nameplate and original ordering record should take precedence when cable length or mechanical dimensions matter.
Product Introduction
The Emerson EPRO PR6423/003-030-CN is an 8 mm eddy-current proximity sensor intended for non-contact measurement on critical rotating equipment. It detects changes in the distance between the probe and a conductive shaft target, allowing the monitoring system to determine shaft displacement, relative vibration, position, eccentricity, or rotational reference information.
The sensor is normally used as part of a complete measurement chain rather than as a standalone PLC sensor. A compatible EPRO converter such as the CON021 conditions the probe signal for the monitoring system, so sensor type, converter, cable configuration, and monitoring input must be checked as one assembly.
PR6423/10R-030-CN
Application Scenarios & Field Pitfalls — Engineer’s Perspective
Engineering Pain Point
The probe itself is only one part of the measurement chain. Incorrect probe gap, incompatible converter, wrong cable configuration, or an unsuitable shaft target can produce a believable signal while shifting the actual displacement calibration.
Typical Applications
- Steam turbines — shaft relative vibration and radial displacement monitoring.
- Gas and hydro turbines — shaft position, vibration, eccentricity, and speed measurement.
- Compressors and gearboxes — non-contact shaft-motion measurement under continuous operation.
- Pumps and fans — machinery condition monitoring where proximity measurement is required.
Technical Pitfalls to Avoid
- Do not confuse PR6423 with a generic 8 mm proximity switch.
This is an eddy-current measurement probe requiring the appropriate EPRO signal-conditioning electronics. A conventional PLC proximity sensor is not an electrical substitute. - Set the mechanical gap according to the correct converter/probe specification.
Emerson’s current PR6423 specification identifies a 0.5 mm initial air gap for the stated measurement specification. Do not copy installation gaps from another probe family or another converter. - Verify the complete ordering code before replacement.
configuration suffixes determine mechanical and cable characteristics. A probe with the same 8 mm tip diameter can still have a different thread, sleeve, cable, connector, or installation configuration. - Check the target shaft material and geometry.
The specified standard target is ferromagnetic steel such as 42CrMo4/AISI 4140, with a minimum shaft diameter of 25 mm. Shaft material, surface condition, diameter, and target geometry can affect the measurement.
Related Products
- EPRO CON021 — compatible eddy-current signal converter used with -family probes.
- — 8 mm eddy-current sensor family for shaft displacement and vibration measurement.
- EPRO PR6424 — related eddy-current sensor family for different mechanical and measurement configurations.
- EPRO PR6425 — larger-system eddy-current sensing option within the EPRO probe family.
- EPRO PR6426 — related proximity sensor family used with compatible EPRO converters.
- EPRO PR6422 — 5 mm eddy-current sensor for applications requiring a smaller probe tip.
- EPRO PR6453 — compatible sensor family referenced with CON021 converter applications.
- EPRO MMS 6000 — machinery monitoring platform used with compatible EPRO measurement chains.
Procurement Check
For a replacement /003-030-CN, verify the complete probe suffix, thread, sleeve length, cable length, connector, hazardous-area approval, converter model, and existing monitoring system.
One important distinction: /003-030-CN should not be treated as a complete vibration-monitoring channel by itself. The probe, compatible converter, cabling, and monitoring input form the actual measurement chain.
If the existing installation uses CON021, match the replacement probe against the original calibration and system documentation rather than selecting solely by the family number.
