21128-13-01 | Bently Nevada Velocity Transducer Housing -29°C to +121°C

What Is the 21128-13-01?

When harsh environments threaten sensitive velocity sensors, the 21128-13-01 from Bently Nevada provides robust protection. This housing is constructed from 303 stainless steel and meets NEMA 4X and IP65 requirements. It resists moisture and corrosion while safeguarding sensors from hose-directed water and physical abuse. The temperature rating spans -29°C to +121°C (-20°F to +250°F).

Key Features & Technical Specs

• Mounting Thread and Cap Option: 13 = 1/2-in 14 NPT with tall cap.
• Cable Exit Fitting Option: 01 = 1/2-in NPT plug.
• Temperature Rating: -29°C to +121°C (-20°F to +250°F).
• Moisture Resistance: Resistant to moisture and corrosion but not submersible.
• O-ring Material: Neoprene.
• Weight: 1.6 kg (3.55 lb) without velocity sensor or fittings.
• Outlet Port Size: 1/2-in NPT.
• Internal Mounting Thread: 1/2-in 20 UNF for 21128 and CA21128.

One distinctive spec is the tall cap option, which enables installation of a Velomitor CT or a 9200/74712 Seismoprobe with isolated base. This flexibility makes the housing suitable for various sensor configurations.

Real-World Applications

In industrial settings where machinery vibration monitoring is critical, the 21128-13-01 excels. It protects velocity sensors in environments exposed to washdowns, corrosive chemicals, or physical impact. For instance, in a paper mill, the housing guards sensors from water and debris, ensuring reliable vibration data. Its IP65 rating allows outdoor or washdown-area use without compromising sensor integrity.

Installation Guide

Mount the housing using the 1/2-in 14 NPT thread with the tall cap. Use the 1/2-in NPT plug for the cable exit. When connecting a Velomitor sensor, cable part number 89477-AA is required. Ensure the housing is properly sealed to maintain NEMA 4X and IP65 protection. For explosion-proof needs, order the CA21128 version with a CSA-approved sensor installed.

Routine Care

Inspect the housing periodically for signs of corrosion or seal degradation. The neoprene O-ring should be checked annually and replaced if cracked or compressed. Avoid submerging the housing, as it is not submersible. Regular inspection per the manufacturer’s manual extends service life and maintains protection.

Common Questions

Q: What is the temperature range of the 21128-13-01?

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

Q: Is the housing submersible?

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

Q: What cable is needed for a Velomitor sensor?

A: Cable part number 89477-AA is necessary to connect the Velomitor sensor to a monitor.

Q: Can the housing accommodate a Velomitor CT?

A: Yes, the tall cap option is required for installing a Velomitor CT.

Q: What is the weight of the housing?

A: It weighs 1.6 kg (3.55 lb) without velocity sensor or fittings.

Product Support & Availability

The 21128-13-01 is in stock and ready to ship from Petro Auto Tech. Contact us for pricing and availability. Please verify current lifecycle status and availability with Petro Auto Tech before ordering.