CMG-3ESP Compact

CMG-3ESP Compact

The CMG-3ESP Compact is Güralp Systems' smallest ever triaxial weak-motion seismometer, offering CMG-3 performance for the price and size of a medium-motion instrument. It is suitable for surface vault (observatory), subsurface vault and temporary installations.

Features

• Covers the complete seismic spectrum with a single transfer function
• 60 s – 50 Hz standard response (with 1s, 30s and 120s options)
• Self-noise below NLNM between 30 s and 16 Hz
• Truly portable: under 9 kg, with lifting handle and convenient access to connectors
• Highly compact form factor, only 168 × 258 mm
• High linearity: >107 dB horizontal, 111 dB vertical (USGS figures)
• Over 140 dB dynamic range over the entire passband (USGS figure)
• Cross-axis rejection over 62 dB
• Sensor axes orthogonal to within 0.1 °
• Robust automatic mass locking, unlocking and centring
• Adjustable feet allow for up to 4 ° tilt
• Low power consumption (750 mW from 10 – 30 V input power)

Options

• Long period response options: 1s, 30s, 60s (default), 120s.
• Short period response options: 50Hz (default), 100Hz, 200Hz.
• Feet allowing 8 ° of sensor tilt.
• Hybrid response.
• For manual mass locking and unlocking, consider the CMG-3ESP.

Noise performance

The noise level of the sensor transducer is at least 20 dB less than the Brownian noise of the instrument (set to −195 dB rel. 1 m²/s⁴/Hz acceleration).

The plot below estimates the system noise power of the vertical component of the 3ESP conventional-response sensor. The red line is the Peterson New Low Noise Model (NLNM).

Measured self-noise of the CMG-3ESP, vertical component.

CMG-3 news

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