21128-01-03 | Bently Nevada 1/2-in NPT Velocity Transducer Housing

What Is the 21128-01-03?

When environmental conditions threaten sensor reliability, the 21128-01-03 from Bently Nevada provides robust protection. This velocity transducer housing is constructed from 303 stainless steel and meets NEMA 4X and IP65 requirements when properly installed. It safeguards velocity sensors from hose-directed water, corrosion, physical abuse, and other adverse conditions.

Part of the 21128 series, this housing is preferred for most non-hazardous environments. Its design includes a 1/2-in NPT outlet port and an unthreaded base with a 28.5 mm diameter. The cable exit fitting option (03) is explosion-proof and includes cable grip fittings, ensuring secure cable management.

Key Features and Technical Specs

• Temperature Rating: -29°C to +121°C (-20°F to +250°F), suitable for extreme thermal conditions.
• Moisture Resistance: Resistant to moisture and corrosion but not submersible, ideal for wet environments.
• O-ring Material: Neoprene, providing durable sealing against contaminants.
• Weight: 1.6 kg (3.55 lb) without velocity sensor or fittings, lightweight for easy installation.
• Mounting Thread: 1/2-in 20 UNF internal mounting thread for 21128 and CA21128 models.
• Outlet Port Size: 1/2-in NPT, compatible with standard industrial fittings.

A unique insight: the 1/2-in NPT explosion-proof cable exit fitting ensures secure wiring in potentially hazardous areas, reducing downtime from cable failures.

Industry Applications

In industries like oil and gas, chemical processing, and water treatment, the 21128-01-03 excels. It protects velocity sensors in areas exposed to hose-directed water or corrosive substances. For example, in a chemical plant, this housing prevents sensor damage from accidental washdowns, extending sensor life and reducing replacement costs.

Additionally, its temperature rating makes it suitable for outdoor installations in cold climates or near hot machinery. The housing’s corrosion resistance is critical for coastal or high-humidity environments.

Installation Guide

Installing the 21128-01-03 is straightforward. First, ensure the mounting surface is clean and dry. Use the 1/2-in NPT outlet port for cable connections. For the 21128 model, the internal mounting thread is 1/2-in 20 UNF. Secure the housing with appropriate hardware, and verify the O-ring (neoprene) is properly seated to maintain the IP65 seal.

When using the 21128 Housing, cable part number 89477-AA is necessary to connect the Velomitor Sensor to a monitor. Always follow Bently Nevada’s guidelines for torque specifications to avoid damaging the housing.

Routine Care and Reliability

To maintain reliability, inspect the O-ring periodically for wear or cracking. Replace it if damaged to preserve moisture resistance. Clean the housing exterior with a damp cloth; avoid harsh solvents that could degrade the neoprene or stainless steel.

Regular inspection of the cable exit fitting ensures it remains tight and corrosion-free. This proactive maintenance prevents water ingress and extends the housing’s service life, aligning with a cost-benefit approach by reducing unplanned downtime.

Compatibility and Integration

The 21128-01-03 is compatible with Bently Nevada velocity sensors such as the Velomitor CT, 9200, and 74712 Seismoprobe. For the Velomitor CT, a tall cap option is required. The housing works with cable part number 89477-AA for sensor-to-monitor connections.

It integrates seamlessly with Bently Nevada monitoring systems, providing reliable data transmission in harsh environments. For explosion-proof needs, the CA21128 version is CSA certified for Classes I, II, III, Division 1, Groups B through G.

FAQs about the 21128-01-03

Q: What is the temperature rating of the 21128-01-03?

A: The temperature rating is -29°C to +121°C (-20°F to +250°F).

Q: Is the 21128-01-03 submersible?

A: No, it is resistant to moisture and corrosion but is not submersible.

Q: What O-ring material does the 21128-01-03 use?

A: The O-ring material is neoprene.

Q: What is the weight of the 21128-01-03 without sensor?

A: The weight is 1.6 kg (3.55 lb).

Q: What cable is needed to connect a Velomitor sensor using this housing?

A: Cable part number 89477-AA is necessary.

Product Support and Availability

The 21128-01-03 is in stock and ready to ship from Petro Auto Tech. Contact our team for pricing and lead times. We provide expert support to help you select the right housing for your application.