There are many issues to become noted regarding behavior of transient current surge suppressors (TVSS) integrating MOVs under over-current conditions.

There are many issues to become noted regarding behavior of transient current surge suppressors (TVSS) integrating MOVs under over-current conditions. With respect to the degree of carried out current, dissipated heat might be inadequate to result in failure, but might degrade the MOV tool and reduce its existence expectancy. If excessive current is carried out with a MOV, it might fail catastrophically, maintaining your load connected, however with no surge protection. A person might have no indication once the surge suppressor has unsuccessful. Underneath the right conditions well over-current and line impedance, it might be easy to make the MOV to burst into flames,[5] the main reason for many fires[6] and also the primary reason behind NFPA’s concern leading to UL1449 in 1986 and subsequent revisions in 1998 and 2009. Correctly designed TVSS products mustn't fail catastrophically, inducing the opening of the thermal fuse or something like that equivalent that just disconnects MOV products.

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