FG5 Features and Specifications

Instrument Features

• Automatic data acquisition and system controller (486 or better based PC)
• Real-Time data processing and mass storage of all measurements
• Environmental monitoring package including automatic logging of barometric pressure, ambient temperature and other system information (requires environment al sensor option).
• On-line gravity corrections for tides, polar motion, atmospheric attraction
• Superspring long period (30-60s) active isolation device
• Patented vertical in-line interferometer (eliminates tilt coupling)
• Built-in collimation optics for verticality alignment
• Drag-free chamber surrounds the freely falling test mass to eliminate air d rag
• Automatic cart servo-controller
• Frequency stabilized HeNe laser (Iodine stabilized HeNe laser option availa ble for highest accuracy applications).
• Rubidium atomic clock
• Turbo-molecular vacuum pumping station
• Ion-vacuum pump with battery backup power supply
• Custom built shipping containers that are shock protected to withstand norm al handling
• Real-time monitoring of dropped object rotation for system diagnostics (req uires rotation monitor option).

General Specifications

• Total shipping weight: 320kg in 6 containers
• Total volume: 1.5 cu.m
• Floor space requirement: 3 sq.m
• Input voltage: 110-240 VAC (switchable), 50-60Hz
• Nominal power requirement: 500W

Performance Specifications

• Accuracy: 2mGal (observed agreement between FG5 instruments)
• Precision: 15mGal/sqrt(Hz) at a quiet site [eg. About 1mGal in 3. 75 minutes or 0.1mGal in 6.25 hours]
• Operating dynamic range: World-Wide
• Operating temperature range: 10 deg C to 30 deg C