Posted by John B [68.69.26.160] on Tuesday, June 02, 2015 at 00:00:04 :
In Reply to: Re: Relays? posted by Keith in Washington [24.41.55.51] on Sunday, May 31, 2015 at 15:48:26 :
OK I will agree with all this info so far. There must be something to it as the manufactures have been using relays for the past few decades, and we are talking mostly 12 volts dc wiring. But how many feet is it from the firewall to the headlights (the biggest load regarding voltage drop) other than the starter motor of a power wagon or jeep sized vehicle is it?
From a guy that has worked at the electrical trade for almost 50 years (the last 28 as an inspector) this automotive wiring is "yes" a different world.
I have worked with mostly ac wiring --- 120/240, 120/208 three phase, 600 delta and Y systems, and up to 500,000 volt distribution systems, and have hipot tested it to 1,250,000 volts. And yes we calculate voltage drop by the foot, by the hundreds of feet, and by the miles.
The only relay I have ever added to any automotive wiring was to my 1964 Oldsmobile Starfire, (not to be confused with the smaller Jetstar.) I added a relay to make the parking lights come on with the headlights. I believe this was the new thing for the 1968 model cars. And yes this did confuse the local boys.
But the main thing is to keep the pistons going up and down and the wheels going round and round. "Happy Motoring."
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