Cable/Connectors Assembly

jpanhalt

Joined Jan 18, 2008
11,088
"Slot for springiness", what does it mean? Is it a way of locking the connectors?
Here's an example where the male contact is slotted and the female is solid. That allows the male to be a tiny bit bigger or slightly flared and be compressed for good electrical contact.

1604327581179.png
 

Thread Starter

waulu

Joined Dec 23, 2016
59
That green strip shown in post #19 is typical of what I was thinking of. Those come in a variety of forms, including ones just made for connecting wires.
Thank you.

Here's an example where the male contact is slotted and the female is solid. That allows the male to be a tiny bit bigger or slightly flared and be compressed for good electrical contact.

View attachment 221249
Thank you for the image.

One last question, what software do you use to do this kind of diagrams? So, to represent cables, connectors, terminations, etc. I was looking for something and I found this program,

https://rapidharness.com/

it seems to produce an intuitive diagram and BOM, that's helpful too.
 

jpanhalt

Joined Jan 18, 2008
11,088
I use an older, paid edition of Eagle (7.x). The new owner (Autodesk, https://www.autodesk.com/products/e...=F360&term=1-YEAR&support=ADVANCED&quantity=1) still offers a free version. KiCad is also popular, but all programs have their quirks and advantages.

You can do the same with Eagle, but Eagle is really designed for PCB's. I have done plumbing diagrams with it though. Maybe what you have is the best for your current project.
 

Thread Starter

waulu

Joined Dec 23, 2016
59
With KiCad/Eagle I would have to create a symbol for the 14 pins miller connector, the Molex Type, the male header, and maybe for the tubular termination. After that, I would use a data bus to represent the cable and connect it to the Molex type connector, the male header, and whatever else there was.

I would have to create a table like this,

1604395310647.png

in another software (Excel/Calc) and paste it in KiCad. I am mainly interested in the columns "Cavity" and "To". But "Color" and "Gauge" is useful too.

In the end, I would have to create the BOM with the cables and connectors directly on KiCad/Eagle. This would be the workflow, right?

I just don't like the data bus to represent a cable but it works. And I would prefer to do everything under one program. But ok, like this I can already do something.
 

jpanhalt

Joined Jan 18, 2008
11,088
Let me start with the heating system for my home. Both of these designs, a "schematic" (left)and a "PCB board"(right) were done with Eagle with the respective subprograms.:
1604396429657.png 1604396302548.png

One misconception people often have when starting out with Eagle or other ECAD is that the "symbol" one needs to create must illustrate what the intended electronic part does. Often, you will see logic symbols, curly lines for coils, and zig zag lines for resistors added. While such symbols are helpful for an engineer to understand what the schematic does, there is no actual need for that detail. The only thing a symbol needs is a name and connections. You can see in the schematic, I did add some of those artistic enhancements. Simple boxes with the right number of connections is all that is needed.

Similarly, the Board part can be used as just a drawing tool.

Now back to your question: Yes, you need to create a symbol for a schematic. However, it does not need to be a scaled drawing of anything. When you name and/or describe your symbol, you create a database for creating BOM's. Then when you use that symbol, it gets added to the BOM for your schematic. There is no need to use another program for that. Eagle will allow you to view and print the BOM. User's have also created several add-ons (ULP's) to do things like export or arrange BOM's and so forth.

In the Eagle schematic, you will be limited in the number of colors you can use for connections. A bus is blue, and a single electrical connection is green. In the board, you have more choices. I don't believe with the older or current free versions that you can use colors for different wires, but you can name them a color and show that name with each just as the schematic I show above does.

There is a significant difference between Eagle and KiCad in how libraries are created. In Eagle, the symbol and package/footprint are linked tightly. If you use Eagle, you will want to make your own library and add it to the libraries that come with the program. I named mine so they always appear as the very first libraries.

Hope this helps.

Edit: spelling
 
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Thread Starter

waulu

Joined Dec 23, 2016
59
I was not expecting that, amazing. You use the schematic and PCB editors like that.

Thank you very much jpanhalt for the explanation and the examples. I will have to gain practise doing that.

Best regards
 

MisterBill2

Joined Jan 23, 2018
8,399
In several hundred electrical circuit drawings over the years I have used only two connector symbols, either an -> # for a male connector pin, or a -< # for a female connector pin. All of the connector details are in the BOM. The wire size and color and wire number are along the line representing the connecting wire.The important details are the pin designations for each and of the cable. Often I also provided a drawing showing the pin designations, always noting if it was the wire side or the pins-side view of the connector. That reduced assembly errors and the cost of rework a whole lot.
 

jpanhalt

Joined Jan 18, 2008
11,088
Once you decide, Eagle, KiCad, whatever, we can discuss connector symbols in more detail. Eagle has several "supply" symbols like the previous poster uses: 1604434611302.png

While useful for some purposes, those single contacts are no different than naming your nets and are not associated with a package or device. If designing a PCB, you probably need a package or device. Package/Device symbols are found in the "connector" libraries. They have one big advantage: They keep the numbering and connection order in order. That can be a big help if you are mirroring a thing to fit on the bottom or top of a board. Also for ERC (electronic rules check) (i.e., is everything connected like you want it to be), it is nice to use a 14-pin symbol and its associated package when that is the connector you will be using. Etc.
 

Thread Starter

waulu

Joined Dec 23, 2016
59
In several hundred electrical circuit drawings over the years I have used only two connector symbols, either an -> # for a male connector pin, or a -< # for a female connector pin. All of the connector details are in the BOM. The wire size and color and wire number are along the line representing the connecting wire.The important details are the pin designations for each and of the cable. Often I also provided a drawing showing the pin designations, always noting if it was the wire side or the pins-side view of the connector. That reduced assembly errors and the cost of rework a whole lot.
That looks like a good strategy yes, keep all the information in the BOM. I will definitely do that. Thank you.

Once you decide, Eagle, KiCad, whatever, we can discuss connector symbols in more detail. Eagle has several "supply" symbols like the previous poster uses: View attachment 221369

While useful for some purposes, those single contacts are no different than naming your nets and are not associated with a package or device. If designing a PCB, you probably need a package or device. Package/Device symbols are found in the "connector" libraries. They have one big advantage: They keep the numbering and connection order in order. That can be a big help if you are mirroring a thing to fit on the bottom or top of a board. Also for ERC (electronic rules check) (i.e., is everything connected like you want it to be), it is nice to use a 14-pin symbol and its associated package when that is the connector you will be using. Etc.
For this project, I will have to use KiCad. Once I start doing that diagram I will post it here to obtain some feedback. Thank you.
 

MisterBill2

Joined Jan 23, 2018
8,399
Those symbols that I presented were used primarily for wired circuits and cable assemblies. Circuit boards have a separate set of symbols.
And there is certainly a big difference between circuit drawings and wiring diagrams. Both are useful, but for different purposes.
 
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