In message <[email protected]>, dated Mon, 10 Dec 2012,
Anthony Thomson <[email protected]> writes:
MOV's can be expected to become warm, hot even, but not to overheat
during normal operation.
My point is that we know the 'little ways' of MOVs, and thus should be
very cautious about them, and assume that they might get very hot.
Even if one does, it should not result in the spread of fire.
Surrounding materials should not support combustion.
>If the supply which they are used to protect approaches the conduction
>voltage of the MOV it will continuously conduct and dissipate way more
>energy than it is designed and rated to do so, and thus become
>extremely hot. And yes, sometimes they do ignite! (Or can ignite
>material adjacent to them.)
Precisely: that might be due to an overvoltage on the mains supply. Rare
but by no means unknown.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
The longer it takes to make a point, the more obtuse it proves to be.
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK
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