Trafo bushing arcing horn specs?
Trafo bushing arcing horn specs?
(OP)
Looking for any info on arcing horns used on trafo MV bushings. Had too many flashovers causing damage to the bushings and now looking for a solution to prevent further/future damage to other installations. Thanx.
Making the smoke come out is easy... getting it back in... isn't!






RE: Trafo bushing arcing horn specs?
Probably you are referring to grading ring or rop-gap device. Beware that rop-gap is presently substituted by Metal Oxide Surge Arrester (MOSA). Rob-gap (arching horn) may not be effective to prevent flashover in the transformer bushing.
Flashover occurs more often by improper surge arrester selection, high level of contamination that exceeds the minimum creepage distance or combination of two phenomena.
RE: Trafo bushing arcing horn specs?
With reference to MOSA's, is the selection dependant on the spec of the trafo itself or does its location on the network play a role, as some of these trafos are moved around on the network a couple of times a year?
Making the smoke come out is easy... getting it back in... isn't!
RE: Trafo bushing arcing horn specs?
In the US the rod-gap is no popular for overvoltage protection mainly because of the weather dependence performance made this device unreliable. In addition, the cost of metal oxide surge arrester is affordable
Here is a product that combine rod-gap and zinc-oxide surge arrester