Introduction
When turbine monitoring moved from periodic manual checks to continuous online protection, the proximity probe became the front line of machine health. The Bently Nevada 146055-20-02-00 belongs to that lineage: a 3300 ceramic capped reverse mount probe built to hold a stable signal in harsh oil, gas, and industrial automation environments. This unit ships as new and original in factory packing, with a 2.0 metre total length and a 3/8-24 UNF thread for reverse mount installations.
What Makes This Probe Practical
The 146055-20-02-00 pairs an alumina ceramic (Al2O3) probe tip with an AISI 304 stainless steel case. That combination resists wear at the target face while keeping the body mechanically stable. The linear range spans 1.52 mm (60 mils), beginning approximately 0.25 mm (10 mils) from the target and running to 1.78 mm (10 to 70 mils), which corresponds to roughly -4 to -16 Vdc. For a 2.0 metre probe, the nominal DC resistance from the center conductor to the outer conductor is 7.88 ± 0.50 ohms.
Key Specifications at a Glance
| Parameter | Value |
|---|---|
| Model | 3300 Ceramic Capped Reverse Mount Probe |
| Part Number | 146055-20-02-00 |
| Total Length | 2.0 m (6.6 ft) |
| Case Thread | 3/8-24 UNF |
| Max Thread Engagement | 0.563 in |
| Probe Tip Material | Alumina ceramic (Al2O3) |
| Case Material | AISI 304 stainless steel |
| Nominal DC Resistance | 7.88 ± 0.50 ohms |
| Linear Range | 1.52 mm (60 mils) |
| Incremental Scale Factor | 7.87 V/mm (200 mV/mil) ±6.5% |
| Operating Temperature | -51°C to +177°C |
| Pressure Rating | 34 Bar (500 psi) nitrogen |
Where It Fits in the Field
A 3300 5 mm system including this probe, a Proximitor sensor, and an extension cable is typically specified for steam and gas turbines, compressors, and large motors. The 2.0 metre length suits reverse mount arrangements where the probe is installed from inside the machine case. The ceramic cap protects the sensing face against target contact, while the 34 Bar (500 psi) pressure seal supports applications where the probe passes through a pressurized housing.
Because the 146055-20-02-00 uses a miniature ClickLoc coaxial connector with standard cable, it integrates into 3300 XL component systems. If you are wiring into a networked monitoring rack, confirm cable runs and any gateway or connection module requirements with your supplier before installation.
Installation and Reliability Notes
Reverse mount probes are threaded into the machine case, so verify thread engagement does not exceed 0.563 in and that the target is AISI 4140 steel for rated accuracy. Keep the probe cable away from high-temperature zones beyond the -51°C to +177°C operating range. During routine outages, inspect the ceramic tip for chips and check the connector for contamination. These simple steps protect signal integrity and extend service life.
Sourcing the 146055-20-02-00
Oil AutoTech supplies ready-to-ship industrial automation spares for oil, gas, and rotating equipment teams. If you need this probe quickly, our team can confirm configuration and dispatch options. Contact Oil AutoTech today for pricing and availability.
