Product Overview

The Bently Nevada CA24701-28-05-20-034-03-02 is a heavy-duty Explosion-Proof Housing Assembly designed to protect proximity probes in the most volatile industrial environments. This assembly acts as a robust external containment system, allowing 3300 XL 8mm probes to be mounted on the exterior of a machine while maintaining a certified flameproof seal.

Constructed from premium 303 stainless steel with a 304 stainless steel sleeve, this housing is engineered to withstand high-pressure washdowns and corrosive atmospheres. It is primarily utilized in oil and gas refineries, chemical processing plants, and power generation facilities where combustible gases or dust are present. The assembly simplifies probe replacement and adjustment by allowing maintenance personnel to access the sensor without disassembling the machine's internal bearing housings.

Technical Configuration

The CA24701 series uses a precise dimensional syntax to ensure the probe tip reaches the target shaft exactly while maintaining a certified explosion-proof barrier.

• Probe with Connector (28): Includes an integrated 3300 XL 8mm proximity probe, pre-configured with selectable hazardous area approvals to meet global safety mandates.

• Probe Cable Length (05): Features a 0.5-meter (20-inch) internal cable lead, optimized for connection within the housing's internal terminal space.

• Standoff Adapter (20): Specifies a 2.0-inch "C" dimension. This adapter provides the necessary clearance between the housing body and the machine surface.

• Probe Penetration (034): Sets the "D" dimension at 3.4 inches. This determines how far the probe extends from the mounting face into the machine to reach the shaft.

• Fittings (03): Provides a comprehensive hardware kit including one 3/4-14 NPT plug, a 3/4 to 1/2 NPT reducer, and a versatile cable seal grip with grommets for various cable diameters (1/8" to 3/8").

• Mounting Thread (02): Utilizes a 3/4-14 NPT mounting thread, required for secure attachment when a standoff adapter is employed.

Technical Specifications

Engineering Installation Guide

Installing an explosion-proof housing requires strict adherence to both mechanical alignment and safety sealing protocols.

Penetration and Gapping

The 3.4-inch penetration depth (Option D) must be verified against the machine's casing thickness. Once the housing is threaded into the machine, use the internal adjustment sleeve to set the probe gap. Typically, the probe is gapped to -10.0 VDC (center of the 80-mil linear range). Ensure the standoff adapter is tightly sealed with industrial-grade thread sealant to maintain the explosion-proof rating of the enclosure.

Cable Sealing

This assembly includes a cable seal grip (Option 03). You must select the correct grommet size corresponding to your extension cable diameter. This seal prevents the passage of explosive gases through the conduit system. Tighten the compression nut until the grommet fully encompasses the cable, ensuring no voids are present.

Engineering Advantages

The CA24701 assembly eliminates the need for internal probe brackets, which can be difficult to service. By moving the probe mounting point to the exterior of the machine, it allows for "hot-swapping" or adjusting sensors while the machine remains in a safe standby state, provided the area is non-hazardous during the specific maintenance window.

The 303 Stainless Steel construction offers superior longevity compared to aluminum housings, particularly in coastal or offshore environments where salt spray causes rapid oxidation. Furthermore, the inclusion of the 3300 XL 8mm probe ensures the highest level of signal stability and resistance to "glitch," providing the reliable data required by Bently Nevada 3500 series machinery protection systems.

Technical FAQs

Q1: Why is the Mounting Thread (Option 02) mandatory for this configuration?

A1: Because this model includes a 2.0-inch standoff adapter, a 3/4-14 NPT mounting thread is required to mechanically couple the adapter to the machine casing while maintaining the flameproof path.

Q2: Can I replace the internal probe without buying a whole new housing?

A2: Yes. The internal 3300 XL 8mm probe is a modular component. However, the replacement probe must match the 0.5-meter cable length to fit properly within the housing's internal dimensions.

Q3: What happens if my cable is slightly larger than the provided grommets?

A3: Do not force the cable. The Option 03 kit provides three different grommet ranges. If your cable falls outside the 1/8" to 3/8" range, you must source a compatible NPT cable gland to maintain the explosion-proof integrity of the assembly.

Q4: Is this housing suitable for underwater applications?

A4: While the housing is highly water-resistant (IP66/IP67 rated with proper seals), it is designed for explosion-proof atmospheric protection, not continuous subaquatic immersion.