Graham Prophet @ eedesignnewseurope.com discuss about a new small seismic sensor from Omron:
Omron Electronic Components believes it has the world’s smallest class size seismic sensor, specifically designed to trigger the shutdown of potentially hazardous or easily damaged systems in the event of an earthquake.
Seismic activity or “Vibrations of the earth” is measured using ProtoCentral’s OpenPressure 24-bit DAQ System.
A geophone is a magnetic device used to measure the Earth’s normal vibrations (some abnormal during events such as earthquakes). These movements are also present when there is a small explosion (commonly used for mining and exploration purposes).
Measuring seismic activity using ProtoCentral OpenPressure – [Link]
Omron announced a new seismic sensor and claims it’s the world’s smallest in size.
D7S sensor is a MEMS 3-axis acceleration sensor featuring OMRON’s unique SI value calculation algorithm, which has a high correlation with the seismic intensity scale that indicates the magnitude of an earthquake and provides higher-precision judgment of seismic intensity scales.
The below diagram describes how D7S works
The sensor has two open-drain outputs INT1 and INT2. INT1 goes active (low) when shutoff judgment condition and collapse detection condition are met (earthquake level 5 or higher), INT2 goes active (low) during earthquake calculations, offset acquisition and self-diagnostic processing.
I2C is used for communication with the sensor for settings and obtaining earthquake-related information.
D7S is a surface-mount compact module with 10.9 × 9.8 mm dimensions. I found the new sensor on Mouser and the price per unit is about $22 (USD) for 1-unit quantity order.