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I would like to make cable schematics for manufacturing that would include:

  • cable lengths
  • connectors
  • pins
  • conduit length
  • heat shrink tube length

and have a BOM for that automatically generated in Altium/Eagle. That that would require every element to be a separate component. Is there a set of commonly used symbols for them? How do you produce such documentation in your projects?

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Cable assembly drawings are essentially mechanical drawings. The electrical connections are secondary to the mechanical construction, and are usually just listed in one or more tables (one for each connector) off in a corner somewhere. While you can use your schematic tool to generate the BOM, the primary drawing is best done in a mechanical drafting tool.

Think about what the person who is going to construct the cable is going to need, if all he's handed is your document. He needs to know

  • what cable to use
  • what connector(s) to use
  • what other elements, such as heat-shrink tubing, need to be incorporated into the assembly
  • what tools need to be used
  • how much cable to cut off the reel
  • how to strip or otherwise prepare the ends of the cable
  • what the assembly sequence for the connector is
  • how the pins of each connector are identiified1
  • finally, which wire in the cable goes to which pin

For simpler cables, all of this information can be put into a single drawing. For more complex cables, there might be several drawings and a separate bill of materials.

Initially, you might be making prototype cables yourself. But if the product goes into production, you'll be handing this task off to another department or a subcontractor, and these details need to be precise in order to avoid expensive misunderstandings.


1 Note that it is important to be explicit about how YOU identify the pins of each connector. The manufacturer's own drawings can be surprisingly ambiguous or confusing.

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  • \$\begingroup\$ Hi Dave! Thank you for the answer! I'm well aware of what information should be included. However I would like to know are there any widely used conventions on HOW should I do it, and what are the recommended tools to do it. \$\endgroup\$ – mactro Jun 9 '16 at 16:36
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I document my cables in a spread sheet. Trying to auto generate a cable diagram takes more work to generate the collateral than simply filling out a template in a spread sheet file. The organization of the spread sheet allows for nice tabular presentation of the data. Here is a sample from a recent project. (This one not fully complete as the final wire specifications are to be specified by a different party).

enter image description here

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  • \$\begingroup\$ Spreadsheet is fine as long as you don't have cases like conduit starting 10cm from left teminal, but only 1cm from right - than it would be nice to have a drawing with dimensions. \$\endgroup\$ – mactro Jun 9 '16 at 10:34
  • \$\begingroup\$ @mactro - I do agree. The spreadsheet also does not lend itself well a harness with more than two connectors. I like to invest my energy in proportion to what is actually required. For anything more exotic than what can be done in a spreadsheet the cable drawing gets generated in a CAD package such as the AutoCad clone called DraftSight. I've also used packages like Visio but have found there is a preference to transfer files around in .DXF format. \$\endgroup\$ – Michael Karas Jun 9 '16 at 11:03

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