21000-28-10-20-039-04-02 | Bently Nevada 8 mm Probe Housing Assembly

What Is the Bently Nevada 21000-28-10-20-039-04-02?

When you need a robust solution for externally mounted proximity probes in hazardous areas, the 21000-28-10-20-039-04-02 from Bently Nevada delivers. This 21000 series housing assembly includes an aluminum body with a 304 stainless steel sleeve, a 3300 XL 8 mm probe with a 1.0 m cable, a 2 in standoff adapter, and a 3.9 in probe penetration. It is rated explosion proof with CSA Type 4 enclosure certification and complies with API 670 standards.

Key Features & Technical Specs

• Probe Type: 3300 XL 8 mm proximity probe with selectable hazardous area approvals.
• Cable Length: 1.0 m (39 in) probe cable for flexible installation.
• Standoff Adapter: 2 in (20) length for proper probe positioning.
• Probe Penetration: 3.9 in (039) with an adjustment range of 13 mm (±0.5 in).
• Fittings: One 3/4-14 NPT plug only for conduit connection.
• Mounting Thread: 3/4-14 NPT for secure attachment.
• Material: Aluminum body with 304 stainless steel sleeve for durability.
• Weight: 1.1 kg (2.4 lb) typical, without fittings.

A standout spec is the probe penetration adjustment range of 13 mm (±0.5 in), which allows fine-tuning of the gap between probe tip and target. This precision helps reduce side-view effects and ensures accurate vibration measurements.

Real-World Applications

In rotating machinery like turbines, compressors, and pumps, the 21000-28-10-20-039-04-02 monitors shaft vibration and position. Its CSA explosion-proof rating makes it suitable for oil and gas refineries, chemical plants, and other hazardous environments. The API 670 compliance ensures it meets industry standards for externally mounted proximity probes.

Installation Guide

Mount the housing assembly using the 3/4-14 NPT thread. Ensure the standoff adapter length (2 in) matches your machine case thickness. For probe penetration lengths between 1.0 and 2.0 inches, counter boring the machine case may be necessary to reduce side-view effects. If the combined C plus D dimension exceeds 300 mm (12 in), add sleeve support near the probe to prevent resonance. The probe penetration adjustment range is 13 mm (±0.5 in).

Routine Care

Inspect the O-rings and thread seal periodically for wear. Verify the probe cable and connector are free from damage. Follow the manufacturer's manual for any maintenance procedures. Regular inspection helps extend the service life of the assembly.

Integration Guide

The 21000-28-10-20-039-04-02 works with Bently Nevada monitoring systems that accept 8 mm proximity probe inputs. It is compatible with standard 3/4-14 NPT conduit fittings. For intrinsically safe applications, pair it with a Bently Nevada barrier or isolator.

Common Questions

Q: What is the maximum probe cable length for this housing assembly?

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

Q: Can I adjust the probe penetration after installation?

A: Yes, the probe penetration option D has an adjustment range of 13 mm (±0.5 in).

Q: Is this housing assembly suitable for hazardous areas?

A: Yes, it is rated explosion proof with CSA Type 4 enclosure certification and available with hazardous area approved probes.

Q: What fittings are included with the 21000-28-10-20-039-04-02?

A: It includes one 3/4-14 NPT plug only.

Q: What is the weight of the assembly?

A: The typical weight is 1.1 kg (2.4 lb) without fittings.

Product Support & Availability

The 21000-28-10-20-039-04-02 is available as new and original in factory packing. Contact Petro Auto Tech for current lifecycle status and availability before ordering.