How To Do The Big 3: Tutorial

[MASTER T KILLA]

Whats a good brand or model posts for 1/0 to go with XS power batteries plan on ordering one to go under my hood.

[YukonDCXL]

I see people saying to run a ground from battery to engine and a ground from battery to frame... I am a little confused now. So I should run a ground from my battery to where the stock ground was on my block and from there to the frame?

[OzzieComm]

I have 2 grounds, both from the negative of the batt.

1 to the block.

1 to the frame/chassis.

[YukonDCXL]

Whats a good brand or model posts for 1/0 to go with XS power batteries plan on ordering one to go under my hood.

I like the Rockford ones. They tighten down super tight and very heavy duty.

[Beast]

a 1/0 guage wire can with stand an easy 250amps of current for bigger lengths. since my length was short(maybe 3-4feet) i went with a 300a fuse even though I only have a 200a alternator. but remember fuse on wire is to protect the wire from catching on fires. Hi this is so funny i happen to have the same exact car may not be the same year but mines a 2000 honda accord ex and im wanting to get a ho alt to put on it and when i looked at this post i was like thats my freaking car! so umm where did you get your alt? mechman dosnt make one to fit the 2.3 accord so i have to go with something else . has the one you have been good? any problems? warranty? oh and thanks i can see that ive done my big III wrong and will fix it this weekend

[AvionicsTek]

I know this thread is quite old, but people are still reading it and probably utilizing it, so I thought I'd point out a couple of issues with this tutorial.

(1) Grounds should not be sanded, because it leaves heavy scratches, and corrosion can form in those scratches around the grounding lug, and work its way under the lug and create a high resistance "bad" ground". Instead, grounds should be PROPERLY burnished with a "bonding brush" such as this...

http://www.browntool.com/Default.aspx?tabid=255&CategoryID=246&List=1&SortField=ProductName%2cProductNumber&Level=a&ProductID=1550.

Chuck it in a drill, insert pilot tip into hole, spin it for a few seconds and check the spot to make sure it's been fully burnished, if not, repeat steps until spot is fully burnished. It only burnishes the area where the lug will make contact, and not only reduce corrosion issues, but also make it look very clean and neat. To further reduce corrosion issues, after the lug is attached, coat it, and the surrounding area, with a coat of clear fingernail polish or clearcoat touchup paint to seal the area from moisture, salt, battery acids, etc.

(2) A question came up early in the thread concerning using a circuit breaker instead of a fuse, to which was shot down on account of a breaker sustaining wear after each trip. For starters, a high quality circuit breaker shouldn't be tripping if you have the correct rating (DC volts and DC amps) of breaker to match the cable current load specs for a given length. If the breaker (or fuse) is popping on an occasional to regular basis, then you need to check you current draw under full load in which the breaker is tripping, and make sure your cable size and breaker/fuse rating is up to snuff for those loads. Remember, breakers/fuses aren't their to protect the equipment (head units, amplifiers, lights, etc.), breakers/fuses are there to protect the wiring. Secondly, it takes a lot of trips on a breaker to wear it out to the point that it can no longer sustain the load that it is rated for and should only be seeing for short spikes at most. If you're using a breaker/wiring combination that is rated anywhere near what you're actually nominally drawing under full load, then, again, you need to upgrade you breaker and wring to well exceed any load that would be continuously drawn through it under full load.

Which leads me to my next point...

(3) Running your wire from the alternator all the way to your battery and then putting a fuse holder there defeats the purpose of the fuse all together. Again... The fuse is there to protect the wiring, so it doesn't make much sense to put it at the other end of the wiring in which it is supposed to protect. The fuse holder should be as close to the alternator as possible, because the alternator is the source of power. If the alternator spikes, it will blow the fuse, almost instantly, a few inches from the alternator, and no harm should come to the wiring. Otherwise, with the fuse being that far from the alternator means that if the alternator spikes (and you're not using appropriately sized wire for the highest of possible loads), it will burn the wiring, melt the fuse holder, and the fuse will probably still be intact after the fire department has left the scene. This is the same reason we put fuse/breaker, for amplifier power cables, are near the battery, and not near the amp. The battery is the power source (or buffer, rather) for the amp, and should the amp spike and overdraw current, it will blow the fuse or trip the breaker at the battery, and leave the wiring intact. So, in short... Cable terminated to positive post on alternator, directly to fuse/breaker close to alternator, then routed from fuse/breaker and terminated at battery's positive post, then wiring from battery positive post is terminated to fuse/breaker close to battery, then wiring routed from battery fuse/breaker and terminated to distribution blocks (near capacitors, amps, etc.), then routed from dist. blocks and terminated at capacitors, amps, etc. DIRECTLY after every power SOURCE (alternator or battery), there should be a breaker/fuse to protect the wiring from that point to the next.

Source experience: Avionics technician/engineer. I routinely deal with aircraft generators that put out anywhere from 100 amps to 120+ KVA ...and right next to all of them is always a panel of current limiters (fuses) or breakers to protect the 4 gauge to 00,000, and 0000 gauge cabling that, at times, costs more than a house for a 200 ft. segment. If one of those fuses pops or breakers trip, it is investigated until the problem is found and remedied. Not only to protect that expensive cabling, but to protect those priceless lives on board. Electrical power is no joke, and is to be taken seriously no matter what size of power source.

[rickman]

i have a question i hear there different ways on doing this big 3 thing, i am planning on getting a high performance alterantor from mechman. so here is the question instead of hooking a ground wire to a chassis can i hook the ground wire to the negative post of the primary battery? another question what kind of fuse amps i would need if the alternator i am planning on getting is 320 amps?

[Nealon14]

Which one of these are better

A) Battery negative post to new chassis ground and battery negative post to engine block

or

Battery negative post to new chassis ground and new chassis ground to engine block.

or it does not matter?

[Karkov]

Which one of these are better

A) Battery negative post to new chassis ground and battery negative post to engine block

or

Battery negative post to new chassis ground and new chassis ground to engine block.

or it does not matter?

This is quoted from Snowdrifter

"Big 3 upgrade as normal:

Alternator ground to chassis/frame

Battery ground to chassis/frame (I like to use a common ground location for the two of these)

Alternator positive to battery positive. You'll hear mixed opinions on this, but personally I like to fuse this one too

Another thing, the facotry charge wire should always come last on the alt stud. 1/0 wire runs should go on first."

[Damian Anthony Lohrenz]

Which one of these are better

A) Battery negative post to new chassis ground and battery negative post to engine block

or

Battery negative post to new chassis ground and new chassis ground to engine block.

or it does not matter?

This is quoted from Snowdrifter

"Big 3 upgrade as normal:

Alternator ground to chassis/frame

Battery ground to chassis/frame (I like to use a common ground location for the two of these)

Alternator positive to battery positive. You'll hear mixed opinions on this, but personally I like to fuse this one too

Another thing, the facotry charge wire should always come last on the alt stud. 1/0 wire runs should go on first."

So what your saying is I don't have to run a wire from engine block to the area where I would sand off for the new ground connection?

So Alternator positive to Battery positive W/ 250Amp Fuse

Battery Ground to new ground location next to battery (Frame)

Then Alternator Negative to new ground location again?