Dual batteries, wired in parallel, will double the hours of useable power. Wired in series, it doubles the voltage out-put. You probably want the extended hours, not 24 volts. Search the threads for how-to diagrams, if you're not familiar with such wiring.
Wil, Tara, Nakeeta (Alaskan husky 6 yr.-old), and Keeko (Jack Russel/Chihuahua mix 3 yr.-old)
(Joey our 6-yr. old Jack Russel mix, passed over the Rainbow Bridge 12/19/09.)
2008 Jay Flight 24RKS; 2006 Chevy Suburban 1500 4X4 Z71
If you installed duel 6 volt batteries you wire positive to negative between the two batteries then connect the trailer to the unused positive and negative terminals. If you installed duel 12 volt batteries you wire positive to positive and negative to negative, then connect one batteries positive post to the trailer and the other batteries negative post to the trailer on the ground side. In either case, charge them just as you use them, both at once. You MUST end up with 12 volts of power in order for everything to work and not burn up your equipment. Both of those wiring schemes will result in 12 volts of power.
Good luck / Skip
2011 F-150 HD Ecoboost 3.5 V6. 2550 payload, 17,100 GCVWR - 2004 F-150 HD (Traded after 80,000 towing miles) 2007 Rockwood 8314SS 34' travel trailer
US Govt survey shows three out of four people make up 75% of the total population
Thanks guys. Don, I'll do it that way.Roy,that's slick,running a Optima Blue Top and a Interstate,it won't be long before it will be needed. I would be using Blue Tops except the new trailer came with a new Interstate.
I really like the setup of two 12VDC batteries using a BLUE SEA 9001E four position (OFF-BAT1-BOTH-BAT2) Battery switch
The three terminal stubs on the back of this switch allows you to use equal length BATTERY CABLES to connect to the two BATTERY TERMINALS. I have my battery banks wired to the battery switch on the POSITIVE BATTERY cable and the NEGATIVE BATTERY terminal battery connection goes to separate FRAME GROUND connections using as short of cable lenght as possible. Both frame ground wiring should be the same length. Both POSITIVE battery cables to the battery switch should be the same short length. ALthough you may hear that you must remove the negative battery terminal when you remove a bettery has to do with having hot battery leads laying around. There is no difference with the battery which leads the switching is done. For me it was more advantages to use the POSITIVE leads for my switching as this provides me with additional positive battery stubs to use for maybe connecting up a Power Inverter or DC Voltmeter connection etc.
Not only does this 9001E switch between the two batteries it also provides an excellent way to be a BATTERY DISCONNECT switch. When in its OFF POSITION both batteries are disconnected and isloated from each other. You will never have to remove a battery just switch it to OFF when you want to totally disconnect the battery bank from the RV Trailer.
Having the capability to disconnect and isolate the two batteries using the four position battery switch allows you to use one battery for something else and also be on a portable charger if you like without disrupting the battery being used for the RV Trailer.
All wiring around this swicth should be at least #4AWG good quality ANCOR Marine brand battery cable with ANCOR brand ring terminals to fit the stud connections. The sealed contacts of the battery switch are make before break and are rated at 350AMPS.
I bought my ANCOR brand cable in 25-foot spools and ANCOR ring terminals from ebay and also got my own 8-ton hydraulic hand crimper kit ($50) and made up my own battery cables.
photos from google images
I am not saying my way of doing this type of 12VDC Battery setup is any better or worse than what others are saying how to do the setup. This is just the way I decided to layout my setup and it works well for me integrated into all of my other 12VDC wiring on my OFF-ROAD POPUP and two way radio operations I am always involved with when operating in the off-the-power-grid type camping routines.
* This post was
edited 05/06/12 11:17am by RoyB *
My Posts are IMHO based on my experiences - PM me Roy and Carolyn
RETIRED DOAF/DON/DOD/CONTR RADIO TECH (42yrs)
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2010 F150, 5.4,3:73 Gears,SCab
2008 Starcraft 14RT EU2000i GEN
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