Transient Voltage Suppressor

Nor can we rely on TVS s (silicon transient voltage suppressors) because the latter often can t even handle the type of energy a single 8/20 xs spike throws at them, least of all a succession of spikes at a certain constant rate per minute. 

Basics of Surge Protector, TVSS, Transient Voltage Surge Suppressor Leonics Technical Catalog http //www.leonics.com/support/article2 7j/articles2 7j en.php. 

Atranszorb or varistor, in combination with a resistor and preferably an inductor, can be added to improve the protection. These semiconductors react within a couple of nanoseconds and limit the voltage. A major problem is that each time a transient suppressor reacts, it degrades. Reliability is therefore poor, rendering this type of device unstdtable for critical apphcations such as tank gauges. 

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