In article
<
CAMmT-dZ57vncGCgRHDD29pyeAYmBVdzfeGtpKwEnCbW1147aqA@...>,
Stefan Trethan
stefan_trethan@... [Homebrew_PCBs]
<
Homebrew_PCBs@yahoogroups.com> wrote:
> Depends on a number of factors such as expected pollution, humidity,
> operating altitude, etc.
> Something under 0.5mm will possibly result in immediate failure.
> Something like 1mm would probably be my design minimum.
> Obviously this is functional insulation only, in other words if this
> insulation breaks down nothing bad must happen except a blown fuse.
> For any kind of safety insulation you would need much more than that.
Thanks. I noted that the 2u2 450V∗ capacitors I bought had a 0.2" pin
spacing and I would have thought more than this would be required. I have
adopted a 0.2" minimum pitch for the tracks and the 0.1" dia pads for the
capacitor means a minimum of 0.1" or 2.5mm between them.
∗ Input capacitors are a pair of 100uF 250V in series with 330k voltage
equalising resistors.
--
Stuart Winsor
Tools With A Mission
sending tools across the world
http://www.twam.co.uk/