Bently Nevada 7400090-055 Proximity Probe Unit

Module Feature

7400090-055 is an eddy current proximity probe of Bently Nevada 3300 series.

It is designed for non-contact measurement of shaft radial vibration, thrust axial position and shaft-to-probe gap. The stainless steel sealed probe head can adapt to oil mist and moderate high-temperature environments. It needs to work together with extension cable and proximity monitor. Widely stocked as spare for power plant turbine, compressor and pump condition monitoring cabinet.

Working principle

The probe head outputs high-frequency alternating magnetic field.

When the conductive metal shaft approaches, eddy current is induced on the shaft surface, which changes the impedance of the probe coil. The monitor converts impedance variation into gap value, and calculates vibration amplitude and position offset for real-time monitoring, alarm and trip protection.

Onboard components

Probe coil, ceramic insulating tip, hermetically sealed stainless steel housing, integral cable and shielding assembly.

LED indicators

No built-in LED indicator.

Hardware self‑diagnosis

Check cable continuity, insulation resistance and probe gap voltage by monitoring rack. No local adjustment function.

Programming software

Not applicable, passive sensing probe, configured via Bently System 1 monitoring software.

Electrical & Process Parameters

Model: 7400090-055 Brand: Bently Nevada Device type: Eddy current proximity probe Function: Non-contact displacement and vibration measurement for rotating machinery shaft

Mechanical & Structure

Mounting: Thread mounting on probe bracket or machine housing Protection class: Hermetically sealed Housing: Stainless steel probe body

Environmental

Operating temperature: -55℃ ~ +177℃ Storage temperature: -60℃ ~ +200℃ Ambient humidity: 5~95% non‑condensing

Certification: CE Status: Original Bently Nevada monitoring spare

Installation

Cut off monitoring rack power before replacement.

Screw probe into mounting bracket, lock the lock nut, connect matched extension cable, set target gap, verify gap voltage and signal reading after commissioning.

Interface

Probe coaxial cable connector, matched extension cable interface.

Diagnostic

Probe fault: Cable open / short circuit, coil damage. Gap voltage abnormal: Incorrect installation gap or target material mismatch. Signal jitter: Vibration of probe bracket or loose lock nut.

Product Brief

7400090-055 probe, Bently Nevada 3300 series eddy current proximity probe spare for turbine and compressor shaft vibration and axial position monitoring replacement.