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I'm starting this thread as more of a learning thing for the general populace out there feel free to contribute comment etc. please keep on point though

the subject speaks for itself and we all have the struggle. parasitic losses hit in many many ways from bad grounds and old weak cables to poorly crimped or soldered connections to improper wire sizing corrosion piss poor design shorts and on and on ......its a tough job keeping ahead of especially because unlike many other things on our vehicle this is happening with time nothing but preventative maintenance and forward thinking can stem the tide of time and then its only a stop gap. here we will discuss connection techniques both in the industry and in our garage

theres bound to be something for everyone here.

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Parasitic loss, what you need to know.

Parasitic loss is an often misunderstood phenomenon. there are actually two kinds that automotive enthusiasts need to be aware of, The kind you can fix and the kind you cant. Parasitic losses occur in every system wire connector bolt blower motor starter and alternator. They can be expressed in terms of resistance or just as ground shunts or plain old piss poor engineering, but they exist and are a constant in any system. The ones you cant control are obviously computers motors lights etc anything you buy as a complete unit hell even switches and relays have a tad of it, why? because you cant get anything for free. Pushing electrons down the line costs a fee in both current (I) amps, and voltage(V) and all because there is no such thing as a perfect conductor. That super expensive 4/0 battery cable you put in that will move 2000 amps in a second without a problem has so much resistance per foot, now granted its a very, very small amount but its still there, and that resistance over the length adds up with every connector every splice every junction and it makes the system pay just a bit to pass through. Which is why a device designed to draw 20 amps as a device might actually draw 212 or 22 amps because its mounted 20 feet away and has to travel a conductor to deliver power which brings us to the point of this article. losses you can control. Examples would be.

using a correct or even oversized conductor to power an accessory. below is a chart that tells you what gauge wire you should run for the voltage, length of run, and load

amp wire size chart.pdf

this is a baseline for accessory installation and should be followed

now as to wire and parasitic loss obviously there are varying quality of materials out there that you should be aware of and depending on the quality you can literally add or remove wire resistance so a smart choice is required . I find it better to purchase a more expensive wire because the materials and coatings will be superior and give longer life.

now lets talk about connectors, believe it or not a bad connection is responsible for more parasitic loss breakdowns and fires than any other single factor in a vehicles dc system. There is a simple test to check for loss as well that moparman1973 posted above and ill repost right here

I dare you to go grab your dvom ( digital voltage meter ) and go test some connectors on your truck, you'll be surprised.

A good quality battery clamp versus a cheapchinnese one can drop as much as 1/2 a volt and add resistance just at the clamp on a new one just imagine what a nasty corroded one will show. a crimp connector can do the same thing with a poor crimp or crap materials and youll be thinkin that looks ok but the meter never lies and seriously it doesn't take but a few bad connections to cause havoc in the system. and as an added annoyance bad connections can even generate stray emf and rf that is really bad for coils and computers.

so what does all this have to do with me and my truck, well simply put a well maintained electrical system will not only make alternators batteries and computers live longer but will also keep the cursing at bay on a cold or hot morning when the key hits and she fires right up verses **** it wont start click click click.

I would also like to point out that bigger isn't always better but most of the time its ok  and as well to a degree you can manage those parasitic losses built in to components by purchasing higher grade parts made by good certified manufacturers . your choice as always OUTLAW7

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I like marine grade wire, it is just a bit larger gauge when calling out number size. It has a good grade copper that you can tell by feel when handling.

 

Marine grade connectors are expensive, but are better copper and is tinned or coated with tin. Always good to add solder to a striped wire end before crimping. I try always use shrink tubing with the adhesive after crimping or soldering the terminal /connector. A heat gun works more evenly and better than a match or small torch to do tube shrinking.

 

Thanks for the write up Outlaw

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Still got my factory OEM cables and done this test and still showing way less than 0.2 volts on all connections. I've been very good about keeping the terminals clean and in excellent shape. 

 

Now like on my old 1982 Honda V45 motorcycle it had ground issues. After some creative re-design I was able to reduce a bunch of voltage loss in the factory designed wiring loom. Basically adding a ground tap in the head and one in the tail which took a bunch of loss off the OEM 1 ring terminal and 16 AWG wire under the fuel tank. :doh:

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see I'm still running my oem cables and I've had to change connectors a few times I'm starting to see a significant amount of black oxidation which means they're near the end of their days so I'm lookin at 2/0 hi count strand with a heavy jacket and then fusion ring eye terminals and heavy duty block post mounts.

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