Now that I am gainfully employed, I can start working on the Bronco again. One of the big projects I will be working on in the next month or so will be converting over to a Dual Battery setup and increasing my Alternator size. I have been working all day sourcing parts and drawing it all out and I thought I would post it up here for comments. The main point of this particular set up to have 2 batteries. I can select either battery to start the truck. I also have a Battery Isolator to keep the charging circuit seperate for each battery. The Main Cranking battery will ONLY start the truck. The Secondary Battery will be a Deep Cycle AGM Battery specifically designed for high powered Stereo operation and depending on the position of the switch will either start the truck and power the accessories or just power the accessories. So here is my design so far.
How this system works:
The alternator sends out a maximum of 240 amps which feeds into the Isolator. The Isolator contains 2 high amp diodes that split the amperage in half, sending a maximum of 120 amps to each output terminal. There is a 1 volt drop across the isolator circuitry, so the A Terminal Voltage sensing wire from the alternator is attached to the output of the primary battery side of the isolator. This will allow the alternator's regulator to account for the voltage drop of the isolator and put enough voltage to the isolator to compensate for its 1 volt drain. Each output terminal of the isolator feeds thru 150 amp breakers. The breakers feed to the battery switch inputs. Each Battery connects its positive terminal to the corresponding input on the battery switch as well. The output of the battery switch connects to the Starter relay on the fender. This allows each battery to be selected to start the truck, or you can select both to start as well. This does not interfere with the charging circuit since the battery and the charge output connect to the same terminal for each battery. The secondary Battery input terminal on the battery switch also connects to the distribution block for the Amps and gets constant power directly from the battery/alternator. The Amp feed will always get power regardless of which battery the switch is selected to.
This system will use the following parts.
Main Battery - Northstar NSB-AGM-34/78 Battery - $297
Sencondary Deep Cycle Battery - XS Power D3400 - Group 34 - Deep Cycle with 3300 AMPS Max output - $270
12V BCI Group 34 AGM Battery, Max Amps 3,300A, CA: 1000 Ah: 65, 2500W / 4000W
Ruff Stuff Group 34 Dual Battery Tray - $85
Alternator - Mechman 240amp T-mount Ford Alternator (Made in the USA) - $350
Isolator - Sure Power 240amp dual battery isolator - $110
Megafuse Holder - New Bolt Mega Fuse and holder 275amp - $17
Circuit Breaker (2) - on each battery lead after the isolator. - $21 x 2
Perko Switch - 8504DP - 250amp switch - $60.17
I found some great information on the load rating on these. Apparently the rating has to do with its explosion proof rating. It will handle a continuous 250 amp load for 15 mins without producing a Arc. So I doubt that will ever happen so I should be able to get by with a standard duty switch instead of the more expensive heavy duty switch. Plus this model locks in the off position, so If I leave town, I can pop the hood, lock the battery switch in the off position and i doubt anyone would be able to steal the truck very easily.
I will probably mount the battery switch with some tamper proof fasteners like these ultra lock screws. That will blow everyones mind.
Power Distribution Block - Marinco 650amp distribution block - $54
Amp Distribution Block - Stinger SHD820 - $29.95
Wiring - #000 AWG alternator to Isolator - $15
Wiring - #1 AWG Isolator to Battery - $20
Wiring - #0 AWG Battery 2 to Battery switch and Distribution Block - $15
Wiring - #0 AWG Wiring Distribution Block to Rear Vehicle AMP Distribution Block - $30
Total System Price = $1412
Crap thats expensive, but I have need for alot of power so its the only way, and I hate doing things half ass and I definitely dont use cheap stuff.