Description
An unthreaded length of 0.0 in (Option 00) and an overall case length of 1.6 in (Option 16) with a 1.0 m total cable length (Option 10) define the specific physical dimensions of the Bently Nevada 21504-00-16-10-02, an 8 mm standard mount proximity probe. This sensor operates on the eddy-current principle, measuring static and dynamic distances between the probe tip and the observed target. Constructed with an 8 mm diameter polyphenylene sulfide (PPS) tip and standard 3/8-24 UNF-2A threads, this configuration does not include lead armor, which allows for maximum cable flexibility and ease of routing through protected conduit systems.
This proximity probe is used in machinery protection systems to perform non-contacting displacement measurements. It is primarily deployed to monitor radial vibration, shaft average radial position, and axial thrust position on critical rotating equipment. When combined with a 7200 Series Proximitor sensor and an extension cable, the system provides a continuous, linear voltage output of 200 mV/mil (7.87 V/mm) across its 80 mil (2.0 mm) calibrated measuring range.
Features
- Option 00 specifies a 0.0 in unthreaded length, meaning the steel probe body is fully threaded for maximum mounting adjustment.
- Option 16 provides an overall case length of 1.6 in, utilizing rugged 3/8-24 UNF-2A threads.
- Option 10 includes an integral 1.0 m (39 in) coaxial cable that maintains calibrated impedance and signal integrity.
- Option 02 provides a miniature male coaxial connector that offers secure electrical termination to a companion extension cable.
- Polyphenylene sulfide (PPS) tip material withstands direct exposure to water, lube oil, and various industrial chemicals.
- Non-armored cable configuration simplifies installation and routing in space-constrained machinery brackets.
Applications
The 7200 Series 8 mm standard mount probe is designed for heavy-industry machinery protection applications, including steam and gas turbines, centrifugal compressors, reciprocating compressors, electric motors, generators, and industrial pumps. It is suitable for:
- Radial vibration monitoring to identify rotor imbalance, misalignment, and bearing wear.
- Axial thrust position tracking to prevent catastrophic thrust bearing failure.
- Shaft average radial position measurements for assessing rotor stability and attitude angle.
- Eccentricity measurements to detect rotor bow during slow-rotation startup.
Ordering Information
| Option Segment |
Code on This SKU |
Description |
| Orderable Part Number |
21504-00-16-10-02 |
7200 Series 8 mm standard mount probe, 3/8-24 UNF threads, non-armored |
| A - Unthreaded Length Option |
00 |
0.0 in unthreaded length |
| B - Overall Case Length Option |
16 |
1.6 in overall case length |
| C - Total Cable Length Option |
10 |
1.0 m (39 in) total cable length |
| D - Connector Option |
02 |
With miniature male coaxial connector |
Technical Specifications
| Parameter |
Specification Value |
| Manufacturer |
Bently Nevada |
| Part Number / Model |
21504-00-16-10-02 |
| Transducer System Type |
7200 Series 5 mm and 8 mm Proximity Transducer System |
| Probe Tip Diameter |
8 mm |
| Thread Type |
3/8-24 UNF-2A standard English thread |
| Lead Armor |
None (non-armored) |
| Unthreaded Length |
0.0 in (0 mm) |
| Case Length |
1.6 in (40.6 mm) |
| Total Cable Length |
1.0 m (39 in) |
| Connector Type |
Miniature male coaxial connector |
| Linear Measuring Range |
80 mils (2.0 mm), begins approx. 10 mils (0.25 mm) from probe face |
| Scale Factor |
200 mV/mil (7.87 V/mm) |
| Scale Factor Accuracy |
Within +/-4% when calibrated as a system; within +/-9.5% with interchangeability |
| Linearity |
Within 0.8 mils (0.02 mm) of a straight line as system; within 2.3 mils (0.06 mm) with interchangeability |
| Frequency Response |
0 Hz to 10 kHz (0 to 600,000 cpm); -5% at 10 kHz |
| System Power Input Requirements |
-17.5 Vdc to -26 Vdc at 12 mA maximum consumption (via Proximitor) |
| Probe Operating Temperature |
-30 degF to +350 degF (-34 degC to +177 degC) |
| Relative Humidity Range |
To 95%, noncondensing |
| Corrosion Resistance |
Unaffected by air, water, lube oil, ammonium hydroxide, sulfuric acid (10%), MEK, or DMF |
| Tip Material |
Polyphenylene sulfide (PPS) |
| Case Material |
Stainless steel |
Installation Guidelines
For optimum measurement accuracy and long-term durability, follow these engineering guidelines during installation:
- Maintain a minimum metal-free clearance of three probe tip diameters (24 mm) around the probe tip to prevent side-clamping and invalid calibration readings.
- Since this SKU has 0.0 in unthreaded length (fully threaded), ensure that the mounting bracket allows the threaded sleeve to pass through and lock cleanly using the supplied jam nuts.
- Ensure the coaxial cable is securely clamped and protected. The minimum bend radius for the non-armored 95 ohm coaxial cable is 1.0 in (25.4 mm).
- Set the probe gap using the system DC voltage. The standard midpoint gap voltage typically reads between -10 Vdc and -12 Vdc on the monitor or Proximitor output terminal.
Compliance and Certifications
The 7200 Series transducer elements comply with standard hazardous area requirements when connected to the appropriate safety barriers and instrumentation. Certified systems carry approvals from:
- CSA, FM, and BASEEFA approvals for intrinsically safe and non-incendive installations.