I have some experience designing circuits over the years but I am working on something I have not done before. This circuit has an AC side and a DC side. The AC side is simple a 5A relay that switches the AC power on and off.
After reading quite a bit on including AC in a DC circuit I see that it is recommended that there be a break between the sides. Meaning that the DC traces do not cross over into the area of the AC traces. It makes sense that you would not want to run a low voltage DC trace close to an AC trace.
What is the recommended space between an AC trace and a DC trace, or how much space should I allot for the separation?
Second question is I am using Eagle Cad and using the autoroute function for most of the board, is there a way to tell eagle cad not to route through a given area?
NOTE: I know hand routing the traces is much better than using autoroute and in most cases I hand route boards. This one is just a bit more than I have time to hand route. Suggestions on a better autorouter are always welcome.
I depends on so many things.
For bare copper and if dirt can get in, or wires could break due to vibrations, then even 5 cm is not enough.
Sometimes a gap in the pcb is used, that prevents a path in the dirt or moisture.
There are ofcourse rules, but if not followed very strict then an error is easily made.
Read about 'creepage' and 'clearance'.
I think the EEVBLOG has hours of video on the subject. For example this one : EEVblog #659 - Medical Plugpack Teardown - YouTube Start at 4:25
tell eagle cad not to route through a given area
You can define restricted areas that the autorouter will stay out of.
Create a polygon using Restricted or Keepout, I don't remember which it is. I experiment on the rare occasions I use it to find the one that works.
My family had an expensive radio of a known brand that stopped working after a few years. It turned out that the wrong glue was used to fix things inside. The glue attracted dirt and that starts conducting.
It depends on various things. As you seem to be on European time you might want to find a copy of the European standard EN 60065 which covers such things.
I may be a bit out of date but creepage distance between open conductors at 230 Vac and parts connected to exposed metalwork used to be 4 mm for class 1 (protected by safety earth) and 8 mm for class 2 (double insulation).
An insulation test should be done at 2 kV for class 1 and 4 kV for class 2.
Of course if you are in a country where the mains voltage is 110 V the requirements are lower.
Russell.