HV tracking across flexible PCB strips

[Chris Elmquist]

On Monday (05/11/2015 at 05:32PM -0400), Noel Chiappa wrote:
>     > From: Jules Richardson
> 
>     > ... "splice tape" is rated for close to 22kV. 
>     > Of course that's *through the tape* though, so although it would
>     > insulate the conductors from the outside world, it's not clear how
>     > effective it would be at insulating the two conductors that are only a
>     > couple of mm apart; the tape doesn't really play a part in that
>     > scenario, only the glue.
> 
> Maybe I'm misunderstanding something, but why not apply a layer of tape
> immediately on top of the conductors - since a thickness of .X of a mm
> (through) will insulate 22KV, Y mm (across - where Y is the distance between
> the conductors) definitely ought to do it.
> 
> Although there is the glue that holds it down - I wasn't sure if that was the
> glue you were referring to, or if you meant some other glue - that might not
> be as insulating (or maybe it is, just don't know).
> 
> But, anyway, if the glue might be an issue, you'd have to apply the tape
> non-glue side down (and stick something like regular electrical tape to it,
> glue-glue, to nullify its glue on the now-up-facing side - unless you want to
> use that to join the two layers of the original together). As to how to get it
> to adhere: if you can figure out what the insulating glue was that they used
> originally, or some modern facsimile thereof, you could use that.

You could also conformal coat it with a spray on HV coating such as,

http://www.all-spec.com/products/CTUFD-12.html?gclid=CjwKEAjwpsGqBRCioKet--bp_QcSJADCtbsb5rmNYHWnzbnkkNcUB_ZsZhxqgXIqeEky9iLLjm7-rxoCd03w_wcB

-- 
Chris Elmquist