Testing for best ground?

[BassAddictJ 5,000+ posts]

besides eyeballing it and finding something part of the frame such as a big metal support as opposed to something like the seatbelt box...... is there any way to test for the best possible ground? when it comes to moving ALOT of current, is it possible to test if one spotis better than another besides just hooking it up and useing that spot?

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[Decipha 10+ year member]

using a battery amperage tester.. if you have one available you can connect it to the ground cable then connect it to the amps battery + cable then try some serious current draws.. if you can pull 200+ amps through with out the unit shutting down i'd say you have a **** good ground

 

[BassAddictJ 5,000+ posts]

using a battery amperage tester.. if you have one available you can connect it to the ground cable then connect it to the amps battery + cable then try some serious current draws.. if you can pull 200+ amps through with out the unit shutting down i'd say you have a **** good ground

i that something i can get done at autozone? i knwo they have aload tester for batteries....but its probly not the same. where i can get access to one of these machines?

 

[BassAddictJ 5,000+ posts]

where can i find one of these amperage puller gimics?

 

[helotaxi 5,000+ posts]

You can do the same thing with a dmm, just measure the DC voltage between the amp ground connection and the battery - terminal. If you get more that about .5V at full tilt on the amp the ground should be improved.

 

[BassAddictJ 5,000+ posts]

You can do the same thing with a dmm, just measure the DC voltage between the amp ground connection and the battery - terminal. If you get more that about .5V at full tilt on the amp the ground should be improved.

cool. i'll measure the bat terminal of the back bat and front bat at full tilt

 

[dleccord 5,000+ posts]

im sure there was a thread like this not too long ago.

but seeing the voltage reading by the amp and by the battery is how i do it too.

 

[BassAddictJ 5,000+ posts]

oh course this needs to be while the amp is playing full tilt right?

 

[helotaxi 5,000+ posts]

Yep. You won't get voltage dropping across the resistance of the ground until you have current flowing through the ground.

 

[BassAddictJ 5,000+ posts]

make sense. well within the next few months im gonan be moving up to 8 runs of 1/0 //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif so hopefully i can find a good spot for all them. I've heard the bottom of the fram is a good spot ussually. i can probly find a good spot near my spare tire well

 

[helotaxi 5,000+ posts]

With that much wire...back to the battery. Your chassis is going to be a shite ground for that kind of current.

 

[RollinGTO 10+ year member]

bus bars are your friend //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[aaron7114 10+ year member]

I read on here a few weeks ago on how to do this with a DMM. It involved putting the positive side of the DMM on the positive on the battery I believe, then the negative on the DMM on the possible ground spot and just find where the the resistance is the lowest to put your ground.

 

[bikinpunk 10+ year member]

With that much wire...back to the battery. Your chassis is going to be a shite ground for that kind of current.

I thought anything over 3 feet for a ground was a no-no?

 

[helotaxi 5,000+ posts]

I thought anything over 3 feet for a ground was a no-no?

Is your amp 3 ft from your battery? If the answer is no, then your ground is longer than 3 feet.