21000-28-05-00-070-01-02 Bently Nevada | Housing Assembly

The Bently Nevada 21000-28-05-00-070-01-02 is a heavy-duty externally mounted proximity probe housing assembly engineered for critical machinery protection systems. Combining a rugged aluminum body with a 304 stainless steel sleeve, it securely encloses an integrated 3300 XL 8 mm reverse-mount proximity probe. This robust assembly provides certified explosion-proof containment and IP/Type 4 protection, making it fully compliant with the American Petroleum Institute (API) 670 standard for turbomachinery monitoring.

Core Technical Advantages

API 670 Standard Compliance

The structural layout meets all strict API 670 design criteria for externally mounted transducer housings, ensuring standardized mechanical form factors, reliable machine casing isolation, and long-term diagnostic dependability.

Explosion-Proof CSA Type 4 Protection

Certified by CSA as a Type 4 weather-proof and explosion-proof enclosure, this unit prevents environmental contaminants from reaching the internal sensor elements while safely containing any potential internal ignition paths.

Optimized Mechanical Configuration

Features a 2-inch standoff adapter combined with a 7-inch probe penetration depth and a 3/4-14 NPT mounting thread option, allowing precise positioning of the internal 0.5-meter probe relative to the target shaft.

Technical Specifications

Installation & Engineering Guide

Mechanical Assembly Constraints

Note that your specified 0.5-meter cable variant restricts the combined maximum dimension of the standoff adapter and sleeve depth to 13.5 inches (34.3 mm). The part and serial numbers of the integrated probe are not visible through this housing length when assembled.

Conduit Sealing and Thread Matching

Thread the dome cover tightly onto the housing body using the integrated O-rings and thread seals to preserve environmental integrity. Torque the 3/4-14 NPT explosion-proof fitting and plug correctly to maintain hazardous area isolation.

Temperature Operating Limits

The assembly maintains a T5 temperature classification when operated within ambient limits of -50°C to +40°C. For hotter environments up to +80°C, the rating transitions to a T4 thermal classification.

Technical FAQs

Q1: Why does this specific model number include an '02' mounting thread suffix option?
A1: The 3/4-14 NPT mounting thread option is a strict engineering requirement for the 21000 series assembly whenever the standoff adapter option is designated as any length other than 00.

Q2: Does the 1.1 kg typical weight specification include all the listed conduit fittings?
A2: No. The 1.1 kg (2.4 lb) specification represents the typical weight of the core aluminum body and stainless steel sleeve structure. External conduit fittings will add minor additional weight.

Q3: Can this housing assembly be utilized for intrinsically safe loop applications?
A3: Yes. When paired with approved proximity probes and connected according to the factory control drawing 140979, the entire circuit functions as a certified non-incendive/intrinsically safe installation.