your grounded...or are you?

[helotaxi 5,000+ posts]

Hopefully those areas where there are overlaps are treated with some type of sealant or they will rust so they are not going to be good condutors if they will pass current at all. Your welder doesn't much care about ground loops, and a volt or two drop won't matter when you are dealing with welding type of voltage so this isn't an accurate comparison, sorry.

 

[DBfan187 5,000+ posts]

HM! Another one of these type of threads. Oh well!

fusion - do what you want, it's your car!:thumbsup

 

[indosia 10+ year member]

1st ground amp to chassis. If you have any problems, run a 2nd ground directy to battery -. If your amps only ground is a wire running from the trunk to under your hood it will have resistance, and cause the amp to oveheat.

 

[maylar 10+ year member]

The battery is one of the worst places for electrical noise. Think of all the accessories that are grounded there - or near there.

Not so. The battery and alternator are the source points, and have the lowest impedances in the system. The closer you get to the battery, the lower the noise. Those "accessories" ground to the body (like your amp), and ultimately return to the source - the battery.

If your only battery ground goes to sheet metal you need to get a new car - your starter is drawing a couple hudred amps through that sheet metal every time you turn the key.

No. Battery goes to engine block (and therefore starter) through a large wire. Alternator negative is also to the engine block through its case. Engine and drive train are isolated from the frame on rubber mounts. Body is also suspended on rubber mounts. The electrical connection from battery/alternator negative is through braided ground straps to the firewall and from battery to a body ground point - usually the fender. That's one of the "magic 3" people upgrade.

What you're arguing would be much the same as claiming the world is indeed flat.

Perhaps you should try being a bit less condescending and maybe learn something yourself.

 

[n2audio 5,000+ posts]

you've got to be kidding me --

 

[buchel 10+ year member]

you've got to be kidding me --

I think you should kill him...

~ Kyle ~

 

[n2audio 5,000+ posts]

I'll be as condescending as I please as long as people are trying to refute some of the simplest, most fundamental principles this hobby has.

You might know this guy...

Originally posted by David Navone at Carsound: Hey, if all the electrical accessories ran a direct line to the negative battery post, it wouldn't be pretty. Here's the deal. You are correct -- copper may be a better conductor than some chassis material. But do you think that any copper wire can compete with the quantity of chassis material? Heck no. There are hundreds of pounds of chassis to compare with just a few pounds of copper. This is why we always use the car's chassis for our power wiring. In fact, it's too bad that have to use copper cabling on our + battery posts.

and this one

Originally posted by Richard Clark at Carsound:Chassis Usually Best Place To Ground Audio Components by Richard Clark

Moderator posted 03-25-2001 08:04 PM

-----the chassis is usually the best place to ground audio components to as it is the lowest resistance conductor in the entire electrical system------and while it may be ok to ground to the battery that only holds true when the engine is OFF----when the engine is on the battery is just another load----connecting to the negative battery terminal would make no more sense than connecting to the negative terminal of a headlight----if your logic was because the battery is considered the source of power when the engine is on the alternator case is really the closest to the actual source of current------but since we seldom have noise with the engine off the battery doesn't seem to be a logical place to ground to------and with the engine on the alternator case is the one place where all the noise current in the car is flowing-------the definition of ground in an electrical system is a point of equal potential---thats why the chassis is the best place---since it is the largest possible conductor it is the place that is most likely to produce this desired condition

more stuff -- http://www.carsound.com/UBB/ultimatebb.php?ubb=get_topic;f=2;t=003840

 

[maylar 10+ year member]

Quoting Richard Clark is like quoting God around here, so I won't bother trying to argue any more, even though there are errors in his logic. Believe what you like.

 

[n2audio 5,000+ posts]

go argue with him about it. I'd like to see what conclusions you come to.

 

[helotaxi 5,000+ posts]

Why bother? He has an even higher opinion of himself than you do of him.

 

[avistar23 10+ year member]

his logic there is very flawed IMO. Running a ground wire of the correct gauge back to your battery is quite a bit better because of resons stated above and no i am not jumping on the band wagon here.

-Mike

 

[indosia 10+ year member]

I get it, your joking.

 

[n2audio 5,000+ posts]

you guys amaze me.

Oh well, I guess you're helping to keep the wire mfg's happy.

 

[indosia 10+ year member]

his logic there is very flawed IMO. Running a ground wire of the correct gauge back to your battery is quite a bit better because of resons stated above and no i am not jumping on the band wagon here.
-Mike

:hilarious

 

[BFers]

Think about it if you ground the Amp in a good place like a rear shock tower bolt or a seat bolt in a unibody car its basicly one peice of metal.

You realize all these "tack welds" have to support the entire weight of the car times 20+ to be certified in a NHSTA crash test.

This is an immense amount of cross sectional area. You attach it to that sheet of metal and that sheet of metal and every tack weld and bolt that contacts it becomes a conductor too. Everything the next peice of metal touches becomes a conductor.

Trust me currents are traveling through more than a few "spot welds". Literally hundreds if not thousands of them...

Its expotental... if you double the cross sectional area of a conductor you QUARTER its resistance.

If it were not the case I wouldent be worried about your amp I would be worried about the car falling apart.