N Cook wrote in message
...
Eeyore wrote in message
...


N Cook wrote:

I get the impression board layout designers just use what has worked
before
as far as track dimensions etc

There are published guidelines for temp rise vs current, copper
thickness
and
track width. You'll find a chart of same in IEC60065 (electrical safety)
in
fact.

The board layout guy will only use the data supplied by the design
engineer.
They're not psychic. Some 'design engineers' have a clue however.


and don't actually consider in great detail
catastrophic failure modes.

Good designers will design for that.


Yes this kit does support the CE mark.

So what's the damn make and model FFS ! Why are you refusing to tell us
one of
the most important pieces of information ?

Graham


I was having a play with track width calculator
http://www.pcbco.com.au/tracecalc.html
and assuming it is still sort of valid
at very high temps.
Putting the melting point of copper of 1080 deg C then for 3.5mm strip of
presumably 1 oz copper then the rupture current would be about 48 amps
which seems reasonable. I knew it must be higher than 12 amps as that
calculation was for round wire. By 1080 deg C we can forget about the
solder
run beefings.
I think I'll leave my 60 amp transformer on the shelf - I'm happy with 48
amps

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/




I think, assuming they survive ordinary power-ups a few times, I'll settle
on a mains side 4 amp anti-surge , with a 5 amp A/S ready to hand spare and
2 off 10 amp quick-blow in the DC lines.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/