Go to the marine supply and buy the multi-stranded tinned "00" gauge.

 

Kaleo
the idea for 2 switches is to allow heavy use on one bat.
while not running the engine and save the second bat. for starting
mhg

 

mhg,
I understand what you mean, but that requires you to manually set the right switches. Using the method I described will automatically isolate the Aux batt when key is turned off. Start van, batts get linked back together and start charging.

Both methods will work. I just think the auto setting method is more user friendly.

I can just imagine Dadvan disconecting his main batt, so he can monitor the radio or whatever. Getting in a pinch and panic because he forgot to flip a switch and the van won't start. LOL

 

Dadvan,
I think 00 gauge might be a little over kill, unless you plan on using the Aux batt to help start the van. Look at what Ford uses in their trailer charge line, no bigger than 8 gauge. You should only need wire big enough to carry the charging amperage to the rear batts. Same idea as trailer batts, they get completly drained some times and are charged through the 7-way when driving.

 

Yea, but if you are going to run a new wire, you might as well go for as little voltage drop as possible and used the tinned marine wire so you never have to worry about corrosion. IMHO. I have a boat so I believe in overkill.

 

All,

I'll probably opt for the "big stuff" as I *MUST* have as little voltage drop as possible due to the electronics. Most amateur radios and laptop PCs get "mad" at 11.8v, even if it's for just a sec (like when you press the transmit key...).

How about ends for the cables? Just use the "standard lead stuff" from Wally World?

DadVan

 

Kaleo, while Kenworth etc use this method because it is cheap it will destroy the batteries. It is best to use an isolator. The reasons the batteries become mismatched is the chemical reactions and buildups that occur in the cells. Eventually one battery will not charge, and before that it's capacity will be reduced over time.

The isolator system is very reliable. You can use a couple of knife switches for a simple backup if something goes wrong.

8 AWG will work for the charging circuit.

A second starter solenoid can be used to start the vehicle from the AUX battery. That gives you a redundant start solenoid also You can engage both switches (key and start button) at the same time for a dual battery start.

If you are going to do it, -do it right!

 

Again, I would get the superior silver leads from the marine supply. Put some dielectric grease on the end, crimp it then some shrink tubing. Your van will be scrap metal before those connections corode.

 

Most people that I know who drive ridiculously huge audio systems have one battery, one large alternator and a big fat 1 or 2 Farad capacitor.

 

jpsarte12,

Yah, but I'm not talking that kind of radio, I'm talking amateur radio transceivers, laptop computers, LCD monitors, video cameras, and other "stuff" related to using the vehicle to chase storms. We frequently drive hours to find the storm, then park the van with all the electronic equipment running, leave it for an hour, then fire it back up and drive for 15 minutes... This process might be repeated a dozen or more times in even a short chase. The big cap you mention helps with the surge loads a "show-sound" system encounters, not with the deep cycle situation I face. In addition, and I know how weird this sounds, I really, really want to keep batteries out of the passenger compartment if at all possible.

DadVan

 

cocot,

I actually live near Smithville Lake (in the Kansas City area). I should be able to drop by nearly any marine store and walk out with the high-quality terminals of which you're speaking?

DadVan

 

Here are a couple of links for the stuff from West Marine.
I am sure any marine place would stock this though.
I would reccomend a Trojan Deep cycle group 31 which is rated at 225 Reserve capacity. Which means 225 minutes @ 25Amp draw.


http://www.westmarine.com/webapp/wcs...120&storeNum=9

http://www.westmarine.com/webapp/wcs...124&storeNum=9

 

Any welding supply store or industrial battery store also has good terminals.

I solder all of my connections after crimping them (no dielectric grease b4 crimp). I then coat them with dielectric grease before assy. I also use lead free battery terminals and solder them. I have seen many problems over the years with internal corrosion inside lead terminals and also the crimped ends on std battery cable ends.

 

I have the 1-1 Fared Cap already. As for ridiculously huge, I'm just getting started. Soon I'll be adding 2 12 disk CD changers & swapping out the VCR for a DVD player. Also going to install an X-box.
As for wanting to add two other batteries, You can't have your engine running in SQ comps when the judges are running your system . It would also be nice to play a DVD when camped out with out having to have your engine running.

 

I got the picture now. That's much different circle from the one I travel in. We try to put the battery in the trunk for better weight distribution at launch and wouldn't think of ading a second battery onboard.