Posted to News on 18th Aug 2014, 15:28
Safety seismic switches protect critical plant and machinery
Sensonics is promoting the SA series of safety seismic switches for high-integrity seismic protection of critical assets and industrial processes such as oil, gas or nuclear installations. Other related products from condition monitoring specialist Sensonics include seismometers, switches and structural monitoring devices. The SA safety seismic switches are a good example of Sensonics' ability to develop innovative seismic monitoring and protection systems that are trusted by the UK nuclear industry; the SA-3 seismic safety switch (pictured) provides triaxial vibration detection and is suitable for protecting vulnerable structures from ground-borne vibration and incorporates a range of safe shutdown options depending on the application.
The SA-3 model features three high-integrity low-noise piezoelectric seismometers positioned perpendicular to each other, together with the associated alarm circuitry, all housed within a robust, weatherproof painted steel enclosure. It is seismically qualified to IEEE-344 (Standard for Seismic Qualification of Equipment for Nuclear Power Generating Stations) and utilises technology that has been operationally proven in harsh environments. The switch operates on seismic events and when the signal from any axis exceeds the preset alarm level, the alarm relay is activated.
Each sensor consists of a system of matched piezoelectric elements arranged in a 'reciprocal' configuration providing a functional test capability. Application of a 1Hz signal to the calibration crystal element mechanically excites the measuring elements, resulting in a defined signal output that can be used to perform a full loop check of the seismic switch.
Such a facility is essential for applications where the switch is located in a hazardous area and requires full-proof testing on a regular basis.
As well as the usual seismic and EMC approvals the SA-3 switch is available for functional safety applications up to SIL-2 and can also be provided in an explosive-proof housing for intrinsically safe applications.
Follow the link for more information bout the SA series of safety seismic switches from Sensonics.
