"DIN rail" or Not

[Richard Wallace]

Originally Posted by squirrel

Yes, you're right, there is some standardization in car electrical systems, as far as components such as fuses and relays and bulbs. Also the computer systems are using a few standard data bus designs. Still, the power distribution parts such as wiring and fuse boxes and whatnot are designed specifically for each model. Have you priced a battery cable for a late model car lately?...

No battery cable, but I did pay about $300 for a new in-tank fuel pump assembly last week. And I know from a fairly recent project that the electric motor in that assembly goes for about $8 in ~1 million piece per year quantities. (I'm a motor designer.) The rest of the assembly is stampings and plastic parts, so its price in service-counter quantities clearly has very little to do with its production cost. And there are nearly as many variations on the design of that component as there are vehicle platforms. However, the quantities required for even one platform are very large, such that the volume leverage on common components like motor armatures, brushgear, and magnets is staggering -- those parts are made in millions per day. And despite my recent frustration at having to replace a fuel pump after only five years of service, I know that statistically my experience in unusual.

All that said, your basic premise is correct: the automotive industry has (so far) missed the opporutunity to standardize basic power distribution system components like fuse panels. Just like FRC robot designers, the automotive OEMs have tended to stick those power distribution parts wherever they will fit after more important design priorities have been satisfied.