Near Intersection of I-35 & I-90 Southern Mn. | I agree with the above discussion. The extra battery can handle the temporary spikes that might be present in a large draw short duration situation. I also agree with the fuse idea and diode idea. The fuse will prevent the flow from the tractor to the separate battery from becoming too great and overloading these lighter wires. The diode will prevent the tractor battery from "pulling down" the separate battery during periods of high load on the tractor battery such as starting. This trick was sometimes used to prevent older electronics from "dropping out" when the tractor was started.
Here's another plan that I saw last year on a complex tillage/fertilizer rig. The rig consisted of a large chisel plow pulling an air cart followed by an NH3 trailer.
This rig was to do tillage, apply dry fertilizer and NH3 in one pass. Since the air cart needed a considerable amount of hydraulic flow to run the blower and metering rolls, large hydraulic lines were run from the tractor over the chisel plow to the air cart.
The air cart also had an alternator and battery system of its own which was driven by the hydraulics. Thus a separate electrical source for the cart electronics was available there. The cart electronic portion was to live "in its own world" with the display cable running back to the tractor.
We added some other electronics to the total rig picture. We used the cart electrical system as the source for the cart and NH3 electronics. The cart electrical system was separate from the tractor electrical system but they did have a common ground.
I'm not completely sure why the air cart had been setup that way but I assume it was partly to avoid the electrical drop on the rather large run which would have been necessary to jump over the chisel plow. Since the air cart needed a large hydrualic flow anyway they probably just decided to add the electrical system. This might simplify the hookup at the tractor end. |
Battery to prevent voltage drop
