Arcing Horn Design Help
Arcing Horn Design Help
(OP)
I need to design an arcing horn that will be used with a 95kV BIL insulator. I am not familiar with the electrical engineering side of things so I was wondering how do I calculate the proper air gap distance between the arcing horns? Also, how does material play a role? I am assuming using copper is ideal.






RE: Arcing Horn Design Help
The only common use for arcing horns these days is for use as arc transfer horns above switch contacts. In such a case, the BIL doesn't have much to do with horn design; the spacing of the throat is near zero, and opens with the main contacts so that the resultant arc sucessfully transfers to the horns which self-extingush the arc. Taper I would expect is more determined by available space than anything else.
I would expect the ultimate width of the horns to be fairly critical, but wouldn't have an idea of what usual practice calls for. It should be noted that many current switch transfer arc horns are arranged so that one arm is spring-loaded to snap open very quickly to sretch the arc as quickly as possible.
If your application is indeed for switch transfer horns, I'd suggest looking at examples. Since most of the switch will be designed based on staying above critical flashover distance to prevent starting phase to phase or phase to ground arcs, but the horns are instead designed to extingush an already existing arc, it would seem that the widest part of the horn needs to be several to many times the critical flashover distance.
RE: Arcing Horn Design Help
RE: Arcing Horn Design Help
ghostbuster7, how did you determine the proper spacing between the two steel balls on the ends? Currently I have 1/4" stainless rods on each end of the insulator with 1.75" spacing. I plan on testing this, but it would be nice to know if there is a standard calculation to follow.
RE: Arcing Horn Design Help
Using arc gaps will lower the BIL of the system (by making the flashover lower than that of an insulator alone) and result in more flashovers and momentary outages (if there is reclosing). There may be fewer permanent outages because of fewer failed porcelain insulators.
RE: Arcing Horn Design Help