SHINKAWA VW-202AL-8 Axial Displacement Sensor
SHINKAWA VW-202AL-8 Axial Displacement Sensor
The SHINKAWA VW-202AL-8 is an industrial-grade non-contact eddy-current displacement sensor probe manufactured by Shinkawa Electric Co., Ltd. Specially designed for non-contact axial position monitoring, thrust bearing wear tracking, and shaft displacement measurements, this sensor delivers continuous high-precision signal feedback in heavy rotating equipment to prevent catastrophic mechanical contact.
Product Introduction / Overview
Operating on the non-contact eddy-current measurement principle, the SHINKAWA VW-202AL-8 displacement sensor monitors minute axial movements of critical machinery shafts relative to stationary casings. When paired with a matching Shinkawa converter or driver (such as the VK series), it converts physical shaft displacement into standardized voltage or current signals, serving as an essential sensor component in API 670-compliant machinery protection systems.
Primary Function: Continuous non-contact axial displacement, thrust position, and shaft position measurement.
Target Machinery: Steam turbines, gas turbines, boiler feed pumps, industrial turbocompressors, blowers, and large electric generators.
Technical Table
| Technical Parameter | Specification / Detail |
| Manufacturer | Shinkawa Electric Co., Ltd. |
| Model Code | VW-202AL-8 |
| Sensor Type | Non-contact Eddy-Current Axial Displacement Probe |
| Tip Diameter | 8 mm nominal |
| Thread & Housing | Full-thread body design (Metric M10x1 / stainless steel body) |
| Linear Measuring Range | Approx. 0.25 mm to 2.25 mm (2.0 mm dynamic range) |
| Linear Sensitivity | Standard 8 mV/µm (200 mV/mil) with matched driver unit |
| Output Type | Direct interface to Shinkawa driver / signal conditioner |
| Target Material Standard | AISI 4140 steel target standard |
| Cable / Connector | Integrated flexible armor cable with miniature coaxial connector |
Environmental Tolerance Conditions
| Parameter | Operational Limit / Rating |
| Probe Tip Operating Temperature | -35°C to +177°C (-31°F to +350°F) |
| Cable & Connector Operating Temp | -35°C to +120°C (-31°F to +248°F) |
| Ingress Protection (IP) | IP67 / Hermetically sealed tip resistant to continuous oil spray |
| Pressure Differential Rating | Tip sealed against internal machine casing pressure up to 0.5 MPa (5 bar) |
| Vibration & Shock Resistance | Compliant with IEC 60068 standards for heavy industrial environments |
Operating Instructions
Safety Protocol: Lock out power to the target machinery and verify the shaft is fully stopped before installation.
Mounting: Thread the probe body into an internal bracket or penetration sleeve. Avoid over-torquing the body thread.
Gap Calibration: Adjust the distance between the probe tip and target shaft face until the output gap voltage matches the system mid-scale value (typically -10.0 V DC at the driver test points).
Locking: Tighten the locknut firmly to prevent probe drift caused by machinery operation.
Connection & Shielding: Connect the coaxial output lead to the extension cable, protecting the junction with insulating heat-shrink tubing to avoid ground loops.
Fault Diagnosis
| Symptom / Fault | Potential Root Cause | Recommended Action |
| Gap Voltage at Maximum / Negative Rail | Open circuit in sensor cable or probe tip disconnected | Inspect coaxial cable continuity; check extension cable connections. |
| Zero Gap Voltage / Constant Near Zero | Probe tip touching target surface or short circuit | Back off probe body; check tip face for physical damage or shorting. |
| Erratic Signal / High Output Noise | Loose locknut, cable shield ungrounded, or ground loop | Verify single-point shield grounding; tighten mounting hardware and locknut. |
| Non-Linear Output / Calibration Offset | Incorrect target material or electrical runout on shaft face | Verify shaft target material matches 4140 steel calibration; check target surface finish. |
Related Models of the Same Series
SHINKAWA VW-202AL-5 (5 mm tip variant for tight mounting spaces)
SHINKAWA VL-202A08L-1A42 Eddy-Current Vibration Sensor Probe
SHINKAWA VK-202A Eddy-Current Displacement Driver / Transmitter
SHINKAWA VK-1422 Signal Conditioner Unit
SHINKAWA FRP-338 / FRP-320 Rack-Mounted Monitoring Modules
Storage Conditions
Storage Temperature: -20°C to +70°C (-4°F to 158°F)
Storage Humidity: 5% to 95% RH (Non-condensing)
Packaging: Moisture-proof anti-static ESD bag with desiccant.
Environment: Dry, climate-controlled warehouse isolated from corrosive vapors, high magnetic fields, and direct mechanical shock