Description

Bently Nevada 18745-02 7200 Series Monitor Module

The Bently Nevada 18745-02, also cataloged as the 18745 dual-channel monitor module, operates as a dedicated hardware component for continuous radial vibration and thrust position measurement within the 7200 Series Proximity Transducer System.

Hardware Specifications

Parameter	Specification
Model	18745-02
Brand	Bently Nevada (Baker Hughes)
Origin	USA
Weight	Approx. 0.35 kg
Dimensions	Standard 7200 series card form factor
Operating Temp	0 deg C to +65 deg C
Storage Temp	-40 deg C to +85 deg C
Humidity	95 % non-condensing
Power Consumption	< 5 W per module
Input Signal	Eddy-current proximity probes (5 mm or 8 mm typical)
Signal Output	4-20 mA or 1-5 Vdc proportional
Buffered Output	Front panel coaxial / rear terminal dynamic output
Relay Outputs	Dry contacts for Alert / Danger, configurable latch mode

Eddy-Current Probe Scaling and Gap Voltage Validation

The 18745-02 applies linearized scaling factors between probe tip displacement and output voltage, maintaining proportional accuracy across the specified target gap range. Gap voltage validation logic continuously samples the DC bias level against a nominal -10 VDC reference, ensuring correct probe standoff before enabling trip signaling. This prevents false machinery shutdown due to probe contact loss or target surface anomalies.

Frequently Asked Questions

Q: Does the module support hot-swap replacement in the 7200 rack?

A: No. The 7200 system backplane does not support live insertion; power must be removed before removing or installing the 18745-02 to avoid transient faults.

Q: Can both channels operate with different probe types?

A: Both channels must use compatible eddy-current transducer types within the same module. Mixing 5 mm and 8 mm probes requires separate configuration verification for each channel's scale factor.

Q: What is the relay switching delay in danger condition?

A: Relay activation occurs within milliseconds after exceeding the configured danger setpoint, subject to any user-set time delay jumper configuration.

Field Installation Guidelines

Install the 18745-02 into the designated 7200 rack slot, ensuring correct alignment with guide rails and backplane connectors. Apply even pressure during insertion to avoid connector pin damage. Use shielded twisted-pair cable for probe signal wiring, grounding the shield at the rack end only to minimize ground loops. Verify gap voltage at each probe prior to enabling monitoring functions. Perform functional testing by simulating probe displacement and confirming proportional output change and alarm relay operation.

Specifications

• Brand: Bently Nevada

Advantages

• High reliability in industrial environments
• Supports continuous operation
• Compatible with major PLC/DCS systems