[ARC5] ARC-5 AC Power Supply solutions

[Brian Clarke]

John is right about isolation. And the subsequent comments that isolation of 
a scramble- or bifilar-wound primary should exceed 300 Vac is not the only 
concern. It is not just your own personal safety at issue, here.

In some countries that are signatories to CE principles, you cannot onsell a 
product you have constructed, even for amateur use, if the primary to 
secondary isolation does not exceed several thousand Volts. You may care to 
check the wiring rules [NEMA, CCITT, AS3000 etc] in your own jurisdiction 
before you commit unknown others, further down the buying chain, to 
potential harm. (If you construct something for yourself and successfully 
kill yourself, then the charge of suicide probably would not hold.)

Such rules in Australia now make it difficult to offer used goods in an 
auction if they do not carry an approval tag showing conformity to relevant 
legislation. So, we are obliged to remove power cords, or to have a suitably 
licensed person carry out the testing and legal tagging. I am not sure that 
offering goods 'As is' absolves the seller from liability; that might need 
testing in a court of law; do we really want to go down that path and merely 
fill the pockets of itinerant wordsmiths?

Solution? Use transformers properly designed and constructed to meet the 
safety regulations in your jurisdiction! Then get your pride and joy tagged 
by a licensed assessor.

73 de Brian, VK2GCE.

"J. Forster" <jfor at quik.com> said on
Wednesday, February 02, 2011 1:51 AM


> Another consideration is isolation between halves of the primary. It might
> not be all that good.