The Bently Nevada 3300/20 is designed to provide early warning of thrust bearing failure by continuously monitoring two independent channels of shaft axial position. It is highly recommended to use a 2-out-of-2 (AND voting) configuration to prevent false trips caused by transducer failure.

Technical Specifications

1. Input & Signal Processing

• Signal Input: Accepts one or two proximity probe signal inputs.
• Input Impedance: 10 kΩ.
• Sensitivity: User-programmable for 200 mV/mil (8 V/mm) or 100 mV/mil (4 V/mm).
• Accuracy: Within ±0.33% of full-scale typical, ±1% maximum at +25°C (+77°F).
• Nominal Consumption: 1.5 watts.

2. Outputs

• Recorder Outputs: User-programmable for +4 to +20 mA, 0 to -10 Vdc, or +1 to +5 Vdc.
• Buffered Transducer Outputs: One coaxial connector per channel on the front panel and one terminal connection per channel on the rear.
• Output Impedance: 100 Ω.

3. Alarms & Displays

• Alarm Setpoints: Alert and Danger alarms are bi-directional and digitally adjustable from 0 to 100% of full-scale.
• Meter Display: Non-multiplexing vertical bargraph LCD per channel; includes a third center scale for Probe Gap.
• OK LED: Indicates the condition of the monitor, transducers, and field wiring.

Ordering Information (Suffix Codes)

Format: 3300/20-AXX-BXX-CXX-DXX-EXX

A: Full-scale Range Option

• 01: 25-0-25 mils

• 02: 30-0-30 mils

• 03: 40-0-40 mils

• 05: 50-0-50 mils

• 06: 75-0-75 mils

• 11: 0.5-0-0.5 mm

• 12: 1.0-0-1.0 mm

• 13: 2.0-0-2.0 mm

B: Transducer Input Option

• 01: 3300 or 7200 Proximitor® systems, 200 mV/mil

• 02: 7200 11 mm (not 3300XL) Proximitor system, 100 mV/mil

• 03: 7200 14 mm or 3300 HTPS Proximitor systems, 100 mV/mil

• 04: 3000 Proximitor® 200 mV/mil (Requires -18 Vdc supply)

• 05: 3300XL NSv and 3300 RAM Proximitor Sensor, 200 mV/mil

C: Alarm Relay Option

• 00: No Relays

• 01: Epoxy-sealed

• 02: Hermetically-sealed

• 03: Quad Relay (Epoxy-sealed only)

• 04: Spare Monitor - No SIM/SIRM

D: Agency Approval Option

• 00: Not required

• 01: CSA/NRTL/C

• 02: ATEX self-certification

E: Safety Barrier Option

• 00: None

• 01: External

• 02: Internal

Field-programmable Jumper Options

• Danger Relay Voting: AND voting (factory default) or OR voting.
• Danger Relay Mode: Normally de-energized (factory default) or Normally energized.
• Alarm Time Delay: 0.1 sec, 1 sec, 3 sec, or 6 sec.
• Thrust Direction: Toward probe or Away from probe