Description

Bently Nevada 330100-90-05 3300 Proximitor Sensor

The Bently Nevada 330100-90-05, also cataloged as the 330100 Proximitor Sensor, operates as a dedicated hardware component for eddy-current probe signal conditioning within 3500 and 3300 Machinery Protection System platforms.

Suffix Breakdown & Model Matrix

The alphanumeric suffix codes define the physical configuration and certification compliance for this specific hardware assembly:

• 90: Total Length Option. Calibrated for 9.0 metres (29.5 feet) of total system length (combined proximity probe and extension cable).
• 05: Agency Approval Option. Multiple Approvals specification for international hazardous area certifications.

Hardware Specifications

Parameter	Specification
Model	330100-90-05
Brand	Bently Nevada
Origin	USA
Weight	0.29 kg
Dimensions	20.4 x 22.2 x 3.7 cm
Power Supply	24 VDC Nominal
Operating Temp	-51 degC to +100 degC
System Length	9.0 metres
Approvals	Multiple Approvals (Option 05)

Eddy-Current Probe Scaling and Gap Voltage Validation

The 330100-90-05 conditions high-frequency RF signals to measure static and dynamic distances between the probe tip and the target rotor surface. During installation and routine calibration, gap voltage validation requires setting the static DC bias point to a -10 VDC target, corresponding to the linear center of the eddy-current probe scaling profile. Cross-talk suppression circuitry minimizes electromagnetic interference from adjacent channels when probes are mounted in close proximity on the machine case, maintaining signal integrity for precise rotordynamics analysis.

Frequently Asked Questions

• Q: What is the critical consideration for matching the 330100-90-05 with cables and probes?
• A: The 90 suffix specifies a 9.0 metres system length. The sensor must be matched with a combination of proximity probe and extension cable that equals exactly 9.0 metres in total physical length to prevent errors in the 7.87 V/mm (200 mV/mil) scale factor.
• Q: Can this sensor be hot-swapped while the machinery protection monitor is live?
• A: No, removing or connecting the sensor under power can cause transient voltage spikes that may trigger false trips on the Machinery Protection System. The channel should be bypassed or the system powered down prior to hardware replacement.
• Q: How does the sensor handle hazardous area classifications?
• A: The 05 option provides Multiple Approvals, which means the device satisfies European (ATEX/IECEx) and North American (CSA) requirements for intrinsic safety and non-incendive installations when installed with approved intrinsic safety barriers.

Field Installation Guidelines

• Mechanical Mounting: Secure the Proximitor Sensor housing to a clean, flat surface inside a weather-proof environmental enclosure. Ensure it is isolated from structural vibrations and high-voltage conduits.
• Shielding and Grounding: Terminate the coaxial cable shield at the designated instrument ground bus within the monitor cabinet. Avoid multiple ground points to prevent ground loops that disrupt the eddy-current measurement.
• Bending Radius: Maintain the manufacturer's minimum bending radius specifications for the extension cable to preserve the RF impedance characteristics of the coaxial core. Do not use sharp bends or tightly cinched zip ties.

Specifications

• Brand: Bently Nevada

Advantages

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