The Prism-SP 10-second period sensor uses omnidirectional components, so the sensor can be installed at any tilt angle with loss of monitoring range.
The Prism-MP and -LP models are also very tilt-tolerant, able to operate at installation angles of up to 15 degrees from horizontal. As with all broadband seismometers with high velocity sensitivity, an insulation cover is recommended to reduce thermal currents that affect sensor drift. With such a small package to cover, a small foam box or a thermal mass such as a hollow concrete block filled with sand will provide the additional stability, particularly when installed in underground vaults as shown the the video below.
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