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nort
03-05-2008, 02:00 PM
I am ready to get everything I need to install an aux battery in my '04 158" under the passenger seat. Does anyone know off-hand how much 4 gauge wire I will need to pick up to go from the main battery to the driver seat to the passenger seat? I know the best way to do it is to measure but thought maybe someone may know and save me some time. If I can save myself a few hours to spend with the kids, it goes a long way with the wife:D: I will be following the pdf instructions that have been posted with the relay under the drivers seat.
Thanks,
Nort

OrioN
03-05-2008, 03:47 PM
If nobody replies, here's how i do it...

I run a string, rope, or old 18g wire along the path, then remove and measure it.

bikerjoe
03-06-2008, 05:28 AM
I don't know the length, but if you are going to run a 4 ga. battery cable INside of your cabin, make sure you have a fusible link at EACH END of that cable in the circuit. You wouldn't want to accidentally set down something and cross that cable with the seat pedestal or anything "ground." Put the link on your main battery, and run your cable from that link to another link, and connect that link to the second battery. That way, if the cable is grounded (a spilled Coke, a dog chewing on it, etc.) you won't set your truck on fire.

mike_mcginn
03-06-2008, 11:45 AM
My 06 was prewired for the aux battery
under the passenger seat. Not sure
about the 04.

manxman
03-06-2008, 11:58 PM
What post describes installation instructions for aux battery and where does one get the relay.............

mobileoilchange
03-07-2008, 12:29 AM
how much wire for aux battery

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I am ready to get everything I need to install an aux battery in my '04 158" under the passenger seat. Does anyone know off-hand how much 4 gauge wire I will need to pick up to go from the main battery to the driver seat to the passenger seat? I know the best way to do it is to measure but thought maybe someone may know and save me some time. If I can save myself a few hours to spend with the kids, it goes a long way with the wife I will be following the pdf instructions that have been posted with the relay under the drivers seat.
Thanks,
Nort

do yourself a favor and dont use 4 gauge. get some 0 or 1 welding wire. its better wire, heavier and cheaper, and you can get it anywhere you buy welding supplies. also its more flexable and easier to use and route.

nort
03-07-2008, 01:23 PM
I don't know the length, but if you are going to run a 4 ga. battery cable INside of your cabin, make sure you have a fusible link at EACH END of that cable in the circuit.

What size fuses should I use? 80amp?

I will stop by the welding store and check prices. I just built some 48"w x9"d x30"t cabinets that will cover the rear wheel wells and may end up putting the aux batteries in there. The heavier wire would probably be a better choice for the longer run.
Thanks for the input,
Nort

mobileoilchange
03-07-2008, 04:27 PM
not to step on bikerjoes toes, but i myself would use a "breaker" instead of fuseable links. with a breaker you just reset it, a fuse or a fuseable link you have to replace.
:2cents:

bikerjoe
03-07-2008, 06:30 PM
not to step on bikerjoes toes, but i myself would use a "breaker" instead of fuseable links. with a breaker you just reset it, a fuse or a fuseable link you have to replace.
:2cents:

You're correct. However, a breaker with a manual reset is desirable. If there is a short, you don't want the breaker to reset itself and attempt to reignite the problem.

For longer runs, welding cable is the BEST choice. Electricity travels on the SURFACE of wire, so a big, thick wire cannot carry as much amerage as 10,000 strands of wire thinner than a human hair. That is a fact! Welding cable is made to carry 600 or 800 amps, making it ideal for battery links. it makes both batteries act like one, rather than the main battery trying to "suck" energy out of the auxiliary battery as it is needed.

It would also be good to put a solenoid in-line, that is energized when your ignition is ON. in this way, the AUX batteries are separated from the main battery while stopped. You can run down the AUX batterie(s) without affecting the main battery.

sikwan
03-07-2008, 06:57 PM
For longer runs, welding cable is the BEST choice. Electricity travels on the SURFACE of wire, so a big, thick wire cannot carry as much amerage as 10,000 strands of wire thinner than a human hair. That is a fact! Welding cable is made to carry 600 or 800 amps, making it ideal for battery links. it makes both batteries act like one, rather than the main battery trying to "suck" energy out of the auxiliary battery as it is needed.

I think this is only true if we're at the higher frequency spectrum notably called skin effect. Since this is DC, it doesn't matter. Solid core or multi-stranded conductors with the same gauge have the same current carrying capabilities. Multi-stranded wins for its flexibility in this application.

lzcamper
03-08-2008, 04:28 PM
I want to put my aux batteries (two 6V AGM) under the floor just in front of the left rear wheel and put a charger/controller under the passenger seat. The cables linking the batteries to the distribution panel will be run under the van and be about 10 feet long. What kind and size cables should I use?

Rick

sikwan
03-08-2008, 04:43 PM
I want to put my aux batteries (two 6V AGM) under the floor just in front of the left rear wheel and put a charger/controller under the passenger seat. The cables linking the batteries to the distribution panel will be run under the van and be about 10 feet long. What kind and size cables should I use?

What kind of currents will the batteries be seeing from the distribution panel?

I would go for at least 4AWG or larger, but this will depend on what you're planning to run. If you can get the larger (smaller numerically) gauge and multi-stranded wire for less, I would do that instead.

Does your charger/controller act like a regulator also, where it monitors the battery voltage and charges the batteries accordingly? Without seeing it myself, it would seem to me that the distance between the batteries and its charger/controller is too far apart. The length of wire will cause a voltage drop and the batteries can be overcharged.

mobileoilchange
03-08-2008, 05:18 PM
thats why i said to use welding cable. its alot better then any battery cable your gonna get. solder the ends on and use heat shrink tube on the ends to seal it and to prevent any bare wire.

lzcamper
03-08-2008, 09:41 PM
Trying to conserve space inside the Sprinter, I bought an Elixer30 (amp) controller/charger that is small enough to fit under the front seat. It has a distribution panel with 2 circuit breakers for AC and 3 fuses for DC and no regulator. I'm going to check to see if it can acommodate a 3 stage charging regulator for the AGM batteries. My Sprinter also has a 90 amp alternator. I don't know how efficiently this (smaller) alternator will handle the charging load.

Rick

bikerjoe
03-09-2008, 08:20 AM
I think this is only true if we're at the higher frequency spectrum notably called skin effect. Since this is DC, it doesn't matter. Solid core or multi-stranded conductors with the same gauge have the same current carrying capabilities. Multi-stranded wins for its flexibility in this application.

On that note ...

http://www.epanorama.net/documents/wiring/wire_resistance.html

and this ...

http://www.thenakedscientists.com/forum/index.php?topic=11914.msg160029;boardseen

so I stand corrected.

ohlsonmh
05-07-2008, 11:02 PM
My 04 has a (factory-installed?) aux battery under the passenger seat - what is it for? Does it back-up the regular battery?

The van was bought "Brand-Spanking Used" from a Dodge dealer, but nobody had a clue about this.

ohlsonmh
05-07-2008, 11:46 PM
Another related (?) question: My van has a timer on the console that the dog steps on looking out the window.

It's some sort of heater - what does it heat? Is it why I have an Aux battery?

Right now, I have it disconnected - afraid the dog will run down the battery if she turns it on while I'm out of the van. The manual says it's some sort of heater, and has instructions to set it, but no clue as to what it's supposed to actually do. Seems to me a heater would use a LOT of battery power.

The thing came on on the middle of the night & scared the he77 out of us! (I have a very simple camping conversion I've built, because we love to travel in a camper, but didn't want to spend a lot or have everything permanently installed, so I made a bed that pops out in a couple of minutes.)

kkanuck
05-08-2008, 01:18 AM
My 04 has a (factory-installed?) aux battery under the passenger seat - what is it for? Does it back-up the regular battery?

The van was bought "Brand-Spanking Used" from a Dodge dealer, but nobody had a clue about this.

Search "Auxiliary Battery" and you will find all the info you ever wanted....

mean_in_green
05-08-2008, 02:15 PM
Another related (?) question: My van has a timer on the console that the dog steps on looking out the window.

It's some sort of heater - what does it heat? Is it why I have an Aux battery?

Right now, I have it disconnected - afraid the dog will run down the battery if she turns it on while I'm out of the van.
.)

Don't worry yourself too much about running the battery down - the heater has a programmable cycle upto two hours max, so it's unlikely you'll ever flatten it.

Sounds like it has a stored programme to come on during the night which was possibly inadvertently activated by the pooch?! You can scroll through the stored programs by pressing P, and alter them to your needs. You'll see a digit 1, 2 or 3 displayed once if set (corresponds to each stored program number). Press P to scroll through the three programs, and once more to switch stored programs off.

MIG

ohlsonmh
05-08-2008, 04:18 PM
Thanks much for the replies :bounce:

That's what happened: the Pooch puts front feet on the buttons to see out & "Programmed" the thing!

But still - what does the thing DO? All we experience is a fan running in the engine compartment - is it supposed to heat the interior? Is it supposed to keep the engine from freezing in winter? Why should I re-connect it? :thinking:

The book doesn't give a clue.

Paul Baier
05-09-2008, 12:44 AM
I don't about the length of the wire, but I would recomend a #2 wire. I have a second battery in the rear and used a #1.