1.Choose connectors,connector 1,and connector 2,or connector 3 and ect.
2.Choose tooling,based on your application field,such as machine and so on.
3.Choose Wire,such as wire structure,UL no. ,color,and so on.
4.Design Wire diagram.
5.Remark tolerance,BOM
6.Other requirement.
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Custom cables assembly design guide
How to design custom cables?