Description

The Bently Nevada 3300/25, also cataloged as the 3300/25 Dual Accelerometer Monitor, operates as a dedicated hardware component for absolute machine housing and structural vibration measurement within 3300 Machinery Protection System racks.

Hardware Specifications

Eddy-Current Probe Scaling and Rotor Dynamics Integration

Configured to augment proximity measurement loops, the module interfaces with casing-mounted transducers while other rack slots execute direct eddy-current probe scaling for fluid-film bearing analysis. Consequently, the monitor resolves high-frequency structural elements that supplement low-frequency shaft relative data. Furthermore, technicians perform gap voltage validation (-10 VDC targets) across adjacent displacement loops to isolate true casing motion from raw rotor dynamics, while internal filtering circuits ensure signal cross-talk suppression between structural and proximity sensor lines.

Frequently Asked Questions

Q: How do technicians adjust the high-pass and low-pass filter settings on the 3300/25 module?

A: Personnel must configure physical plug-in jumpers directly on the monitor circuit board. The hardware architecture supports over 10,000 distinct high-pass and low-pass filter combinations to adapt the channel response to specific machine casing dynamics.

Q: Is there an installation density restriction for the 3300/25 monitor within a single chassis?

A: Yes, due to the cumulative power consumption profiles of the connected external accelerometers, a single 3300 system rack must contain no more than eight 3300/25 monitor modules simultaneously.

Field Installation Guidelines

• Chassis Insertion: Place the module into any available chassis slot from Position 3 through Position 14. Do not attempt installation in Position 1 or Position 2, which are dedicated to the power supply and system monitor.
• Terminal Torque: Tighten all rear terminal block wiring screws to a maximum specification of 0.56 N-m to prevent loose electrical connections under continuous structural vibration.
• Shield Grounding: Terminate the coaxial or triaxial accelerometer cable shields at the designated chassis ground bus bars. Do not allow the shield to ground at both ends, avoiding the formation of ground loops.
• Conduit Routing: Maintain physical separation between the transducer signal leads and any high-voltage AC power distribution wiring to prevent inductive noise coupling.