Chris Jones wrote:

http://www.andy-duke.co.uk/roost/Non...2006_05_14.png

Maybe when you replace the switch, rewire it in series with the HT
fuse - that should allow arcs to extinguish at switch off.


.... Phil


Also, if you can get a 2-pole switch that fits ok, then wiring the two
sets of contacts in series ought to improve the ability to extinguish
the arc, (for a given contact separation etc.).


** If you look at the schem, the HT fuse is in the rectifier ground path where the voltage and current levels drop to zero at twice the supply frequency.

So for a couple of mS each 10mS, there is not enough of either to sustain an arc.


.... Phil