Hi,
I’m quite new to KiCad, I’ve created one PCB so far that was a copy of an existing PCB that we didn’t have the layout files for. I’ve got some schematic drawings to do, they aren’t PCBs but cabinet wiring diagrams, I thought I could use Eeschema.
My question: is it possible to get Eeschema to show not connected crossing wires with a “bridge” rather than a flat crossed wire ? like this: http://www.ibiblio.org/kuphaldt/electricCircuits/Ref/01048.png
I think not. Never come across that option before.
No, but for electrical wiring you’re better off using a tool specifically for that. You can bludgeon an ECAD schematic editor to make the diagrams but it’s really much easier to use electrical diagram tools and you get nicer results.
Hi,
thanks for the replies and confirmation that I can’t do “bridged” non contact crossing wires.
I have the same need for KiCAD in between PCB designs as the original poster RaptorUK.
I have created a simple 2-pin schematic part which consistents of a small arc connecting the two pins, so the whole thing takes up 4 grids of a 1.27mm grid size. The arc radius is 1 grid, so the semi-circle ends up 2 grids in diameter. I set the part name and reference fields to invisible.
The result looks like this, where two of my little schematic symbols are being used to jump over another wire:
http://postimg.org/image/qnuza5s1x/
It works great for me!
Hi Kyran,
that looks like a good workaround, thanks for posting the idea.
regards, Simon
This is something that just makes wiring much clearer. It would be nice to have it automatically jump around non-connections as stated in this path. If memory serves, ADS can be made to do this. This is my defacto circuit simulation reference as it seems to be the most powerful in my work. That being said, Cadence and Altium are also very nice. My work is typically in the microwave regime and above though.
There was a time when printers and copiers were cruder, that the bridge symbol could easily smudge to look like a junction.
This is why any sensible company schematic drawing standard forbids placing junctions at crossing wires and insists on two “Tees” with a small offset. Then two wires crossing can safely be assumed to be not connected
I think that was one of the “house rules” every place I ever worked.
A few places take it a step farther, Where the wires join at a “Tee”, the last 0.1" (5 mm) or so will be bent at a 45 degree angle.
Dale
that ‘bent’ style connection sounds like a standard “bus wire connection” way of doing a line connection
Don’t worry, this is only the the schematic drawing standard of the “sensible” companies. The rest of us are free to do it properly. 
In my opinion, junction dots should not be an entity that the user has control over. That is the user should not be able to add/delete them. Eeschema should display them automatically where two lines connect other than at their end points or where more than two lines connect, Currently it will display a junction dot when you connect two wires like a ‘T’ but then you can remove the junction dot and break the connection. Eeshcema shows the unconnected endpoint but when zoomed out this looks like a dot. A very difficult problem to find, but it gets worse. Draw another wire so they connect like a ‘+’ thinking that all wires now connect at that point, however you actually have two unconnected wires.
Another scenario, draw two intersecting wires like a ‘+’, place a dot at the intersection, they are now connected. Remove the dot, are they still connected? No. If you place your cursor at the intersection and press delete the “Clarify Selection” dialog will show there are two wires. Put the dot back and grab an end point of one of the wires and extend the it a bit. Remove the dot, are they still connected? Yep! Again, place your cursor at the intersection and press delete, you now have four wires all connected at that intersection but no dot.
With the user being able to add/remove junction dots it’s just too easy to end up with a schematic and netlist that do not match, and it can take a bit of digging to find out why.
I agree that junction dots should really be automatically created when wires are joined and removed when a wire segment is deleted. I don’t like orphan junctions. I would also like junctions to be three segments and no more. The rule against junctions at crossing wires is just about universal as @dchisholm noted
It is not the job of any EDA to enforce any particular rule/style/standard no matter how universal you may think it is. While you should be free to follow any convention you like, the rest of us should also be free to follow any convention we like. For instance, it would be quite annoying if we could not draw multiple ground connections to a single point to indicate that the PCB should be laid out the same way. Some circuits, such as transistor amplifiers etc, are more recognizable/readable when drawn symmetrically.
Personally I see no benefit to limiting connections to 'T’s only so long as either dots or bridges (I prefer dots) are used properly.
Rules concerning junction dots and bridges have been around since the days of drafting boards and mylar film layouts but that certainly doesn’t make them “universal”.
Allowing four or more segments as an option, but making three the default would satisfy all of us
Yes, but then we start down the slippery slope of everyone wanting options to enforce this convention or that convention. As I mentioned, it is not the function of the EDA to enforce conventions, but it should be flexible enough to support any convention. Some would argue that automatically displaying junction dots is enforcing a convention. But KiCad aleady makes a half baked attempt to do this and it doesn’t seem to bother anyone. Perhaps because junction dots are “just about universal”.
If you are going to have junction dots then they should work properly. With properly used dots there is no need to disallow ‘+’ connections.
What we have at the moment is a bit clumsy, not removing junction dots when the number of wire segments is less than three and allowing dot deletion making joined wires to look like a crossing.
One way of dealing with emphasising a star ground would be to have a many, eg 6 or 8 way, star symbol, associated with a through hole pad footprint
Can always creat one as a symbol and drop it in.
This is an ancient thread from 2015, which was V4 days. Any discussion is unlikely to be very relevant now.
Closing it.
(EDIT by eelik: search for “junction dots” if you want to know more. Good for entertainment, too.)
