Configured for reciprocating machinery vibration analysis in 3500 monitoring systems, the Bently Nevada 3500/70M 176449-09 (3500/70M Recip Impulse Velocity Monitor) provides direct physical and electrical execution of seismic transducer signal conditioning and mechanical fault detection.

Model Identification

• Model: 3500/70M

• Part Number: 176449-09

• Product Type: Recip Impulse Velocity Monitor

• System Family: 3500 System

Hardware Specifications

Mechanical Monitoring & TSI Integration

The 3500/70M module utilizes specialized signal processing to monitor high-frequency impulse acceleration and reciprocating velocity. Eddy-current probe scaling is not applicable for this seismic-input module; however, signal path calibration is required to align transducer input with crankcase or crosshead vibration signatures. Gap voltage validation is irrelevant for seismic inputs, but installers must perform sensor sensitivity checks to confirm transducer input signals reach the module within specified linear ranges. Cross-talk suppression is maintained through internal channel isolation, preventing signal corruption in multi-channel reciprocating compressor installations.

Ordering Info

• One (1) 3500/70M Recip Impulse Velocity Monitor.

• Appropriate I/O module for seismic sensor termination.

• Technical documentation for configuration and signal processing logic.

Field Installation Guidelines

• Module Insertion: Ensure the 3500 rack power is isolated before inserting the module into the designated slot to prevent backplane bus surges.

• Seismic Wiring: Connect seismic transducers to the I/O module using shielded cabling to reduce electromagnetic interference (EMI).

• Grounding: Secure the rack to the system ground bus to prevent ground loops, which can distort low-level seismic vibration measurements.

• Logic Mapping: Use the 3500 Rack Configuration software to map sensor inputs to the required measurement parameters for reciprocating machine components.

Frequently Asked Questions

• Is the 3500/70M hot-swappable? Yes, the monitor supports hot-swapping within the 3500 rack system, provided the procedure aligns with local maintenance safety protocols.

• Can this monitor handle non-reciprocating machinery? The module is purpose-built for reciprocating compressor dynamics; utilizing it for rotating equipment may yield incorrect data due to signal processing logic.

• How are alarm setpoints managed? Setpoints are defined within the 3500 configuration software based on the measured impulse and velocity thresholds.

• Are sensors included with the module? No, the module is a signal processing monitor; seismic transducers must be procured and installed separately.

• What is the purpose of the impulse velocity parameter? It allows for the detection of high-frequency mechanical impacts typically associated with crosshead, valve, or rod-drop faults.

• How do I verify channel operation? Utilize the 3500 Rack Interface Module (RIM) diagnostic screens to confirm channel "OK" status and real-time vibration values.

• Can I monitor four different machine points? Yes, the four channels are independently configurable, allowing monitoring of four distinct vibration measurement locations.

• Is the monitor backward compatible? It is compatible with 3500 systems; however, verify the rack firmware version against the module requirements in the technical manual.