The SIGMA family of robust Force Balance Accelerometers rounds off Gaiacode's suite of seismic instrumentation. Based on a newly designed sensor with a truly rectilinear suspension of the inertial mass, SIGMA instruments have a flat response to ground motion over a very large frequency range. With their exceptional performance, SIGMAs are suitable for local and regional strong motion recordings and for earthquakes engineering applications.
SIGMA Standard Version
The standard product of the SIGMA family of FBAs is a three component analogue instrument, capable of measuring ground accelerations of up to 4g. It is designed to be deployed in vaults or shallow surface installations. Packaged in a rugged vessel of anodized aluminium its three components are oriented in the classical orthogonal configuration.
The SIGMA digital is an easy to use digital output force balance accelerometer. It is based on a SIGMA Standard seismometer mated with a 8-channel, 24-bit TAU digitizer. Together these units are housed inside a waterproof enclosure of anodized aluminium. The 8-channel 24-bit digitiser exploits the high dynamic range exceeding 170 dB of the truly rectilinear sensors forming a perfect portable digital accelerometer.
The SIGMA Downhole is a slim line three component accelerometer, packaged in a stainless steel housing, sealed with double O-rings. Its stacked three sensors are based a inertial masses with truly rectiliniear suspension systems. It is versatile, as it can be used as a posthole or a borehole instrument, rated for wet boreholes down to a depth of 300 m, depending on the type of cabling and connectors used.