TheBently Nevada 87890-01is a central system monitor for the3300 Seriesvibration monitoring system. It ensures rack integrity by managing power-up sequences, voltage health, and system-wide reset functions. Featuring a 2-secondPower-up Inhibitto prevent nuisance alarms and supporting both AC and DC power inputs, this module provides the foundational safety and diagnostic oversight required for critical rotating machinery.
Technical Specifications
Part Number:87890-01
Manufacturer:Bently Nevada
Product Type:System Monitor (3300 Series)
Power Supply:18-36 VDC / 85-264 VAC
Power Consumption:< 15 Watts
Voltage Monitoring:+VRH, +VRL, +7.5V, +5V, REF, -7.5V, -VT
Power-up Inhibit Duration:Approx. 2 Seconds
Operating Temperature:-20°C to +65°C
Weight:2.8 kg
Country of Origin:United States
Key Features and Engineering Advantages
Intelligent Power-up Inhibit:Automatically suppresses alarms for 2 seconds during startup or voltage drops. This prevents "nuisance trips" that can occur as electronic components stabilize, ensuring the machine only trips during genuine fault conditions.
Comprehensive Voltage Diagnostics:Continuously monitors seven critical internal voltage rails. The front-panel"SUPPLIES OK"LED and internal diagnostic LEDs allow technicians to verify power integrity at a glance, simplifying troubleshooting.
Flexible Power Input:Compatible with a wide range of power sources (85-264 VAC or 18-36 VDC), making it suitable for global industrial standards and diverse plant power architectures.
External Bypass Functionality:Supports an external contact closure to bypass all monitors and disable alarms. This is essential during specialized maintenance or testing routines where the rack must remain powered without triggering machine shutdowns.
Centralized System Reset:Provides both a physical front-panel switch and remote terminal connections (on the Power Input Module) to clear latched alarms and reset the system OK relay.
