21128-02-02 | Bently Nevada 3/4-in 14 NPT Velocity Transducer Housing

What Is the 21128-02-02?

When harsh environmental conditions threaten the integrity of your velocity sensors, the 21128-02-02 from Bently Nevada delivers robust protection. This velocity transducer housing is constructed from 303 stainless steel and is engineered to resist water, corrosion, and physical abuse. It meets NEMA 4X and IP65 requirements when properly installed, making it a reliable choice for non-hazardous applications.

The 21128-02-02 features a 3/4-in 14 NPT mounting thread and a 1/2-in NPT explosion-proof cable exit fitting. It operates within a temperature range of -29°C to +121°C (-20°F to +250°F) and weighs 1.6 kg (3.55 lb) without the sensor or fittings. The neoprene O-ring material ensures a secure seal against moisture and corrosion, though the housing is not submersible.

Key Features & Technical Specs

• Constructed from 303 stainless steel for durability and corrosion resistance.
• Rated for NEMA 4X and IP65 environments when properly installed.
• Mounting thread and cap option: 3/4-in 14 NPT.
• Cable exit fitting: 1/2-in NPT explosion-proof fitting.
• Temperature rating: -29°C to +121°C (-20°F to +250°F).
• Weight: 1.6 kg (3.55 lb) without sensor or fittings.
• O-ring material: Neoprene for moisture resistance.
• Internal mounting thread: 1/2-in 20 UNF for 21128 and CA21128 models.

Industry Applications

The 21128-02-02 is ideal for protecting velocity sensors in demanding industrial settings. It is commonly used in manufacturing plants, oil and gas facilities, and water treatment operations where exposure to hose-directed water, corrosive substances, or physical impact is a concern. By housing the sensor securely, this enclosure helps maintain accurate vibration monitoring and reduces the risk of sensor damage. For explosion-proof requirements, the CA21128 version is available with CSA certification for hazardous locations.

Installation Guide

Installing the 21128-02-02 requires proper alignment of the mounting thread and cable exit fitting. Use the 3/4-in 14 NPT mounting thread to secure the housing to the machine surface. The 1/2-in NPT cable exit fitting accommodates the sensor cable, and for Velomitor CT sensors, a tall cap option is necessary. Ensure the O-ring is properly seated to maintain the IP65 seal. For non-hazardous areas, standard installation procedures apply; for hazardous locations, follow the specific guidelines for the CA21128 version.

Routine Care & Reliability

Regular inspection of the 21128-02-02 housing ensures long-term reliability. Check the neoprene O-ring for signs of wear or cracking, and verify that the cable exit fitting remains tight to prevent moisture ingress. The 303 stainless steel construction resists corrosion, but periodic cleaning with a damp cloth is recommended to remove surface contaminants. Avoid submerging the housing, as it is not designed for underwater use. Following these simple steps helps extend the service life of both the housing and the velocity sensor inside.

Compatible Systems

The 21128-02-02 is designed to work with Bently Nevada velocity sensors, including the Velomitor CT and 9200 or 74712 Seismoprobe models. When using the 21128 housing, cable part number 89477-AA is required to connect the Velomitor sensor to a monitor. For explosion-proof installations, the CA21128 version must be ordered with a CSA-approved velocity sensor pre-installed. The BA42608 housing is available for BASEEFA-approved installations requiring compliance with BS EN 60079 14.

FAQs about the 21128-02-02

What is the temperature rating of the 21128-02-02?

The 21128-02-02 operates within a temperature range of -29°C to +121°C (-20°F to +250°F).

Is the 21128-02-02 submersible?

No, the 21128-02-02 is resistant to moisture and corrosion but is not submersible.

What material is the 21128-02-02 housing made from?

The housing is constructed from 303 stainless steel for durability and corrosion resistance.

What cable is needed to connect the sensor to a monitor?

When using the 21128 housing, cable part number 89477-AA is necessary to connect the Velomitor sensor to a monitor.

Does the 21128-02-02 come with a tall cap option?

Yes, the 21128-02-02 is available with a tall cap option, which is required for installing a Velomitor CT or certain Seismoprobe models.

Product Support & Availability

The 21128-02-02 is in stock and ready to ship from Petro Auto Tech. Contact our team for pricing and availability. We are your trusted source for Bently Nevada industrial automation parts.