Sentinel is a premium-quality accelerograph that was conceived for strong motion and structural monitoring with budget-sensitive constraints.
The onboard MEMS triaxial accelerometer is synchronously sampled up to 1000 sps at a resolution of 20bit and exhibits a dynamic range > 85dB and a self-noise < 18µg/√Hz.
The integrated memory bank (32 ÷ 256 GB) allows you to manage a ring-buffer for long continuous recordings as well as event data.
The data format is MiniSEED.
The system implements sophisticated trigger criteria (STA/LTA and threshold) that distinguishes false events (i.e. environment vibrations) from true seismic events.
The internal GNSS receiver allows you to create a network where all the instruments are synchronized with the absolute time.
You can connect to Sentinel locally via network (LAN or WiFi) or, alternatively, remotely using the internal HSPA modem (optional).
The instrument can be used as a stand-alone unit to record seismic events in the field (i.e. Accelerometric Network), or it can be used in a MASTER-SLAVE based monitoring network where multiple instruments are connected to each other; Sentinel is compatible with both the Triton and Atlas and this can be useful when a superior dynamics are needed, for example, as a near field unit.
Thanks to the SeedLink protocol, Sentinel is compatible with the most popular seismic analysis software: Seiscomp3, Antelope, Earthworm.
Sentinel is powered by an external DC source (5 ÷ 16 Vdc) and it is equipped with its own internal battery (LiPo) which can guarantee an autonomy of 5 hours in case of a blackout. The battery is a standard 18650 and can easily be replaced. The internal HSPA modem (optional) is backed up by the internal battery.
Sentinel can be equipped (optional) with 3 relays output and used as a seismic switch, to shut down sensitive equipment such as elevators, pumps, gas valve or to drive alarm systems like sirens or lights.
The instrument comes in an anodized aluminum case which is rugged and shock-resistant and thus suitable for field applications. Sentinel is designed with an adjustable mounting plate in order to simplify the instrument leveling.