I’m trying to create a copper pour for an isolated ground. The pour should have a minimum isolation clearance of 2.0mm, but when I set the clearance in the Copper Pour dialog to 2, all clearances are affected. I need the clearance between this pour and pads/tracks to be the standard 0.25mm.
Is there a way to do this without ‘hacky’ keep-out zones? I guess the only way is to change the geometry of the ‘outer’ pour, but I like to prevent that as you can’t move a ‘part of’ a pour around when shuffling your component blocks around.
There’s no easy way to do that in v5. The advanced design rules system is under work for v6, you can follow it in Need some guinea pigs for a rule-based DRC <<PROTOTYPE>>. (The link is to a post in the middle of the thread on purpose, the new syntax was announced there.) This should give some idea about how it will be done in v6. At the moment there’s no other GUI than the text editor.
Until then, you have to live with some “hacky” workaround.
Ralph, a routed slot would either make this piece of PCB fall off, or still causes the planed to be too close together at the bridges between the slots)
JeffYoung, I don’t really understand you. As you see in my screenshot the isolated plane is already a higher priority than the large plane otherwise it would not create the gap.
eelik, I don’t understand you. What you point at is of course part of the isolated electronics, and I said in OP that the clearance there must be 0.25 (just like the thermal clearance, which is a separate parameter).
You just need the slot where the high voltage may be a problem. E.g. through the center of an optocoupler.
What voltage clearance are you looking at?
As I recall, 2mm with solder mask is good for > 200 volts.
But not enough to meet EN/UL 60950.
Pollution level 2 is right for most indoors equipment.
Then it depend on your board material, FR4 is IIIa, which means 5mm for reinforced insulation at 250Vac
