Winter items to do on the tractor...

Charlie_Iliff · Dec 16, 2005

Bob Rip
I think you're right. If I ever do anything with this project, it will most likely be a 400 amp golf cart controller, a high-speed golf cart motor , and a 48V golf cart battery system. Lots of inefficiencies and fit problems to solve before I think of buying anything.

MossRoad · Dec 16, 2005

Why you want electric, anyway? Fumes bother the animals(and peoples, too)? Just curious. /forums/images/graemlins/wink.gif

J_J · Dec 16, 2005

Have you considered those electric scooters that PT makes. They should be able to pull a small cart.

Charlie_Iliff · Dec 16, 2005

Why you want electric, anyway? 
Ever try to reason with horse people? Internal combustion engines are for outside only!
Electric is good - non-polluting - quiet
And if I really do it well, I can have something almost as good as a stock PT 180 for only a few thousand conversion charge. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

Charlie_Iliff · Dec 16, 2005

those electric scooters that PT makes. 
I looked at them when I was there last. They look fine for getting around a level plant floor. Basically, they're one battery and a starter motor, so I suspect their real working time is minimal. I want a front-end muck bucket dumper that will dump into a trailer or pickup, and forks to carry 8 bales of hay at a time (350 or so lb.)
So far just some random thoughts and notes.

MuncyBob · Dec 16, 2005

8 bales at a time...sounds like you have a barn full of hay burners! The PT has made my "horse work" much easier on my back!! /forums/images/graemlins/grin.gif

BobRip · Dec 16, 2005

Would you still use the hydraulics and have an electric motor drive the hydraulic pumps? This is probably the simpliest way, but there will be a fair amount of energy lost in the hydraulics.
Of course another approach would be an electric motor on each wheel and a separate motor for the other pumps. Or maybe one motor for the wheel pump and one for the steering and lift. I am not sure you would want to run the PTO on electrics. That takes upto about 15 hp. Would you care to describe how you are going to set this up.

Bob Rip

toolz_not_toyz · Dec 17, 2005

This sounds like an interesting and possibly worthwhile project. I would keep the hydraulics and ditch the gas engine. The trick will be getting enough battery capacity in the room you have left over and I bet that's going to be pretty tough. The PT 180 will probably also end up weighing more than it did with the engine...which is good and bad.

Someone made a comparison to forklift batteries. Maybe MR? Anyhow, we used to run our high reach forklifts 24hrs. That required changing the batterypacks, which probably weighed about a ton. The forklift assisted with this by being able to hydraulically eject the pack, then you had to manually lift it off using what was basically an engine lift. Anyhow, the point is this: forklifts use a lot of cells in order to accomplish what they do. You need something smaller.

You need to work out calculations: find a motor that would drive the hydraulics, find out energy consumption, determine the required battery capacity. And then go through that again and again until you have something that would fit.

The next question would be: can you do this economically?

BobRip · Dec 17, 2005

The best batteries have about 4% as much energy as a comparable weight of gasoline. I do some design work on devices that use batteries, and they really limit your energy available. Ways to save energy that you would not bother with on an AC or engine powered device become very important when you run off batteries.

Good luck.
Bob Ripley

Charlie_Iliff · Dec 17, 2005

The next question would be: can you do this economically? 
The answer to that, of course, is a resounding "NO!" But, that's not the objective. (It's hard to beat a small gas engine for power to weight and power to dollar ratios.)
My current thought is to use a high-speed golf cart motor driving the hydraulics for the wheels, lift and steering, and dispense with the PTO. An electric motor at each wheel would be more efficient, and a golf cart axle at each end with two drive motors is an option if a single controller would run both. Driving the hydraulics with one electric motor is simpler, since PT already has all the hydraulics sorted. Very rough computations say I should be able to get a couple of hours with a 12 HP golf cart motor, with a 250AH 48 volt 4-battery pack but that may be optimistic. There may be a small fork lift battery, but what I've seen so far are large, heavy and expensive.
I've not gone very far with real number crunching. Just winter speculating.