Out of 22 Pm's this evening when I got home. Three were from people pointing out that I might need to think about what it takes to handle 40 amps of current. One said I should use a trace calculator.
I can only guess that this is because when I am showing the picture of the front of the express people think they are looking at load carrying traces and that I have undersized them.
I have attached a picture of the back of the layout to hopeful remove the concerns. I use the same rules when every I layout a high voltage design. These come from the UL standards for trace clearances and the ANSI recommended minimums for trace sizing. These are very conservative as in most standards the 20 amp of one side would call for about 350 mils , ANSI asks for 429 mils, mine are 450 mils. This is considered at a allowable temperature rise of only 10 deg C (again conservative). UL calls for the traces separation to be 47 mils and this is the limit I used.
For the 4 amp max traces on the channel feeds most would accept 31 mils, ANSI asks for 39 mils, I used 60 mils.
The large traces in the image are the only current carrying traces on the PCB.
I feel the design is begin done with a very conservative eye. I hope this helps put any concerns to rest.
But if anyone has input they think I am overlooking feel free to PM me. Hopeful like this I can show it is OK, and if not you could help me prevent a problem.
I want to thank the three that PM me to warn me of the serious requirements of copper a current that high would require.
RJ