OverView a sort-of HOME page
Updated 05March2005 - This is the 20th century; in case u didn't know.
This overview is to convey what is involved in the "Battery Project".
Another site is the mobile radio station, see RigProject for more details...
At present I only have two sites showing stuff that I have done to the cruiser.
Be advised that Detail, Page and Fig diagrams do not follow on this web site, they are for my original schematic diagrams in the design phase. My brain sometimes gets ahead of my drawings. Documents should print out on one page only; if they don't - oh well? Pictures are detailed and will download slowly.
The main idea is to install dual batteries in the 1994 USA spec Landcruiser, with out messing with the electronics of the original Toyota design. In particular, the dual charge circuit must allow charging to full voltage with minimal voltage drop. A dual diode charging will not work on the cruiser; and to make a long experiment short I found the Hellroaring unit to be the answer. This unit uses a certain type of transistor(s) that have high current capacity and low forward voltage drop, making the unit opaque to the alternator of the cruiser.
The fuse links in the cruiser are not to my specifications and required modifying. At the same time that the dual battery project is being conceived, thought must turn to fuse links, 12 volt buss system, winch control and how to integrate same. The fuse link problem presented by Toyota is that it is designed not to be messed with by the user and the leads are too short to extend to where one wants them to be. They also have a tendency to kink up, which really puts a bind on their current carrying capacity; i.e., they can develop hot spots and burn through, opening the current path and killing the cruiser - booo on that! It will be noted that the MAIN fuse link runs a lot of stuff including the computer, which draws approximately 11.23 milliamps. If this lead (fuse link) is opened while the engine is running it is possible to blow the alternator. The fuse link is about a #10 wire connected to a #6 wire directly to the battery and the alternator. The battery is the MAIN alternator load through this lead (fuse link). Fuse links are oversized on purpose.
Of course, one must consider why am I doing dual batteries in the first place. Well, I have a bull bar with a 10000 pound Warn winch. The winch can pull about 400 amps under heavy load. My big worry is will one Odyssey (PC925MJT) really run the cruiser and the winch too? Not really. So, one must use two batteries. Experiments have shown however, that one of these batteries will run the cruiser and pull a large log (25 feet long by about 2 feet in diameter; really heavy) up a 45 degree hill for about 150 feet. When I switch the Hellroaring unit to dual battery position it really hauls ass. We have recently (Jan2005) had some minus 5 degree F. temperatures here in Denver and one Battery will start the cruiser in about 6 rur-rurrrs, Battery voltage around 8.5 volts to start engine.
The only long range problem so far is maintaining factory spec 12.81 volts during engine off periods; I'm not sure why the voltage drops to around 11.8 volts over time (the computer only pulls 11.3ma), but I will figure it out someday.
More detail pictures are forthcoming...
More later...
Updated 05March2005 - This is the 20th century; in case u didn't know.
This overview is to convey what is involved in the "Battery Project".
Another site is the mobile radio station, see RigProject for more details...
At present I only have two sites showing stuff that I have done to the cruiser.
Be advised that Detail, Page and Fig diagrams do not follow on this web site, they are for my original schematic diagrams in the design phase. My brain sometimes gets ahead of my drawings. Documents should print out on one page only; if they don't - oh well? Pictures are detailed and will download slowly.
The main idea is to install dual batteries in the 1994 USA spec Landcruiser, with out messing with the electronics of the original Toyota design. In particular, the dual charge circuit must allow charging to full voltage with minimal voltage drop. A dual diode charging will not work on the cruiser; and to make a long experiment short I found the Hellroaring unit to be the answer. This unit uses a certain type of transistor(s) that have high current capacity and low forward voltage drop, making the unit opaque to the alternator of the cruiser.
The fuse links in the cruiser are not to my specifications and required modifying. At the same time that the dual battery project is being conceived, thought must turn to fuse links, 12 volt buss system, winch control and how to integrate same. The fuse link problem presented by Toyota is that it is designed not to be messed with by the user and the leads are too short to extend to where one wants them to be. They also have a tendency to kink up, which really puts a bind on their current carrying capacity; i.e., they can develop hot spots and burn through, opening the current path and killing the cruiser - booo on that! It will be noted that the MAIN fuse link runs a lot of stuff including the computer, which draws approximately 11.23 milliamps. If this lead (fuse link) is opened while the engine is running it is possible to blow the alternator. The fuse link is about a #10 wire connected to a #6 wire directly to the battery and the alternator. The battery is the MAIN alternator load through this lead (fuse link). Fuse links are oversized on purpose.
Of course, one must consider why am I doing dual batteries in the first place. Well, I have a bull bar with a 10000 pound Warn winch. The winch can pull about 400 amps under heavy load. My big worry is will one Odyssey (PC925MJT) really run the cruiser and the winch too? Not really. So, one must use two batteries. Experiments have shown however, that one of these batteries will run the cruiser and pull a large log (25 feet long by about 2 feet in diameter; really heavy) up a 45 degree hill for about 150 feet. When I switch the Hellroaring unit to dual battery position it really hauls ass. We have recently (Jan2005) had some minus 5 degree F. temperatures here in Denver and one Battery will start the cruiser in about 6 rur-rurrrs, Battery voltage around 8.5 volts to start engine.
The only long range problem so far is maintaining factory spec 12.81 volts during engine off periods; I'm not sure why the voltage drops to around 11.8 volts over time (the computer only pulls 11.3ma), but I will figure it out someday.
More detail pictures are forthcoming...
More later...