The Bently Nevada 21504-00-56-05-02 is a high-performance 8 mm proximity probe designed for non-contact vibration and position measurement. As part of the 7200 Proximity Transducer Systems, this probe delivers accurate shaft relative vibration data for critical rotating machinery. Its rugged construction and wide temperature range make it suitable for both steam and gas turbine applications.
The 21504-00-56-05-02 features an 8 mm tip diameter with standard case configuration and 3/8-24 threads. The unthreaded length option is 0 mm (00 suffix), while the overall case length measures 5.6 inches (56 suffix). Total length comes to 0.5 metre (20 inches) with a tolerance of +0.13 metre and -0.05 metre. This model includes a miniature male coaxial connector (02 suffix) for easy system integration.
For output performance, this probe delivers a calibrated range of 80 mils (2.0 mm), beginning at approximately 10 mils (0.25 mm) from the probe face. The scale factor is 200 mV/mil (7.87 V/mm) with ±4% accuracy when calibrated as a system. Linearity remains within 0.8 mils (0.02 mm) of a 200 mV/mil straight line under system calibration. Frequency response spans from 0 to 10 kHz (0 to 600,000 cpm), with only -5% deviation at the upper limit.
This probe requires an input power of -17.5 Vdc to -26 Vdc at 12 mA maximum consumption. The operating temperature range for the Proximitor is -60°F to +212°F (-51°C to +100°C), while the probe and extension cable withstand -30°F to +350°F (-34°C to +177°C). Relative humidity tolerance reaches up to 95%, non-condensing.
Additionally, the Bently Nevada 21504 probe offers excellent corrosion resistance. Its operation remains unaffected by direct contact with air, water, lube oil, ammonium hydroxide, sulfuric acid (10%), MEK (methyl-ethyl ketone), or DMF (dimethylformamide). This chemical compatibility makes it highly suitable for harsh industrial environments.
Temperature sensitivity for this model is typically -3% change in scale factor at +150°F (+65°C) at a 50 mil gap (1.27 mm). When calibrated as a system, the probe maintains ±9.5% accuracy including interchangeability errors. Linearity including interchangeability errors stays within 2.3 mils (0.06 mm) of a 200 mV/mil straight line. Therefore, the 21504-00-56-05-02 delivers reliable performance even under fluctuating thermal conditions.
The probe connects seamlessly with Bently Nevada Proximitor and extension cables. Its miniature coaxial connector ensures secure signal transmission while minimizing noise interference. For optimal results, always calibrate the probe, cable, and Proximitor as a complete system.
Proper installation begins with cleaning the threaded hole and applying anti-seize compound to the 3/8-24 threads. Then, carefully insert the probe until the tip reaches the desired gap. Use a gap meter to set the initial air gap between 10 and 80 mils for best linearity. Tighten the locking nut securely to prevent movement during operation.
When routing the cable, avoid sharp bends and keep it away from high-voltage sources. The 0.5-metre total length provides flexibility for most mounting configurations, though extension cables are available if longer runs are needed. Always verify the probe's serial number and part number are visible for proper documentation.
1 x Bently Nevada 21504-00-56-05-02 proximity probe (8mm, with miniature male coaxial connector)
1 x Locking nut (3/8-24 thread)
1 x Protective cap for shipping
1 x Calibration certificate (system calibration optional)
1 x Installation instruction sheet
Shipping Method : FedEx, UPS, or DHL (door-to-door delivery)
1. What is the calibrated range of the 21504-00-56-05-02?
The calibrated range is 80 mils (2.0 mm), starting from approximately 10 mils (0.25 mm) from the probe face.
2. What cable length does this probe have?
The total length is 0.5 metre (20 inches) with a tolerance of +0.13 metre and -0.05 metre.
3. Is this probe suitable for high-temperature environments?
Yes, the probe and extension cable operate from -34°C to +177°C (-30°F to +350°F).
4. What connector type does this model use?
It uses a miniature male coaxial connector (suffix 02) for reliable signal connection.
5. Can I use this probe with chemicals like sulfuric acid?
Yes, the probe resists direct contact with 10% sulfuric acid, MEK, DMF, lube oil, and several other common industrial chemicals.
| Brand Name | |
| Model No. | 21504-00-56-05-02 |
| Product Type | Proximity Probe |
| hasMerchantReturnPolicy | Adjust according to reality |
| Shippingdetails | Adjust according to reality |
