21000-28-10-20-050-04-02 | Bently Nevada 8 mm Proximity Probe Housing Assembly

What Is the 21000-28-10-20-050-04-02?

When vibration monitoring in hazardous environments demands robust protection, the 21000-28-10-20-050-04-02 from Bently Nevada delivers a certified solution. This proximity probe housing assembly combines an aluminum body with a 304 stainless steel sleeve, offering durability and corrosion resistance. It is part of the 21000 series, designed for externally mounted proximity probes in industrial automation systems.

Engineered for explosion-proof applications, this assembly supports a 3300 XL 8 mm probe with selectable hazardous area approvals. The 1.0 m (39 in) probe cable length and 5 in probe penetration provide flexibility for installation in tight spaces. With a typical weight of 1.1 kg (2.4 lb), it is lightweight yet rugged for continuous operation.

Key Features and Technical Specs

• Probe Option: 3300 XL 8 mm probe with selectable hazardous area approvals.
• Probe Cable Length: 1.0 m (39 in) for flexible routing.
• Standoff Adapter: 2 in (20) for precise positioning.
• Probe Penetration: 5 in (050) to reach measurement points.
• Fitting Option: One 3/4-14 NPT plug for conduit connection.
• Mounting Thread: 3/4-14 NPT (option 02) for secure installation.
• Material: Aluminum body with 304 stainless steel sleeve for corrosion resistance.
• Weight: 1.1 kg (2.4 lb) typical, without fittings.

A distinctive spec is the 8 mm probe size, which enables high-resolution vibration sensing in tight machinery spaces. This precision helps detect early bearing faults, reducing unplanned downtime.

Industry Applications and Use Cases

In oil and gas refineries, the 21000-28-10-20-050-04-02 monitors rotating equipment like pumps and compressors. Its CSA Type 4 enclosure and explosion-proof rating make it suitable for Class I Division 1 Groups C and D areas. Similarly, in petrochemical plants, this housing assembly withstands harsh chemicals and extreme temperatures from -50°C to +80°C (T4 rating). For power generation turbines, the 5 in probe penetration allows access to deep measurement points without compromising safety.

Installation and Mounting Guide

Mount the assembly using the 3/4-14 NPT thread option for a secure fit. Ensure the standoff adapter (2 in) is correctly positioned to align the probe tip with the target surface. The 1.0 m cable must be routed without sharp bends to maintain signal integrity. Always verify that the conduit fitting (one 3/4-14 NPT plug) is tightened to prevent moisture ingress. Refer to the manufacturer's manual for torque specifications.

Maintenance and Reliability Tips

Regularly inspect the O-rings and thread seal for wear to maintain the explosion-proof seal. Clean the dome cover and body with a dry cloth to remove debris. Check the probe cable for cuts or abrasions, especially near connection points. The aluminum body and stainless steel sleeve resist corrosion, but periodic visual checks ensure long service life. Follow Bently Nevada's recommended inspection intervals for optimal reliability.

Compatible Systems and Integration

The 21000-28-10-20-050-04-02 integrates with Bently Nevada vibration monitoring systems that accept 3300 XL 8 mm probes. It is fully compliant with API 670 Standard for externally mounted proximity probe housings. The assembly works with both 21000 aluminum and 24701 stainless steel housings for intrinsically safe applications. For North American installations, CA21000 and CA24701 housings are certified for explosion-proof use.

Frequently Asked Questions

Q: What is the probe cable length for the 21000-28-10-20-050-04-02?

A: The probe cable length is 1.0 m (39 in), as specified by the suffix code 10.

Q: What hazardous area approvals does this housing assembly have?

A: It is CSA certified for Class I Divisions 1 and 2 Groups C and D, Class II Divisions 1 and 2 Groups E, F, and G, and Class III, with enclosure Type 4 ratings.

Q: What is the probe penetration depth?

A: The probe penetration is 5 in (050), allowing access to deep measurement points.

Q: What material is the housing body made of?

A: The body is aluminum with a 304 stainless steel sleeve for corrosion resistance.

Q: Is the 21000-28-10-20-050-04-02 compliant with API 670?

A: Yes, it is fully compliant with the American Petroleum Institute's API 670 Standard for externally mounted proximity probe housings.

Product Support and Availability

The 21000-28-10-20-050-04-02 is in stock and ready to ship from Petro Auto Tech. Contact our team for pricing and lead times. We offer factory-sealed new units with full warranty support.