IH Cub Cadet 582
Electric Conversion - Part 1 ...
Aug 2008
The summer of '08 has been just
a blur of mind-numbing oaf-like labour,
but I finally have gotten ahead of the mundane to start into a project that has
evolved through the self-discipline of in-action.
With a minimal effort and a
small expenditure I was able procure this International Harvester Cub-Cadet 582
rolling chassis in the early summer of 2004.
This is the inventory image that
is standard practice for most capital expenditures that exceed about $100 or so.
About a year later this late
50's early 1960's Westinghouse/Marketeer industrial personal transport unit came
into my possession.
I could write a separate
web-page on the horse trading that it took to pry this mass of rusty but still
functional steel and lead from the grips of a chiseling yard-master someday.
In the fall of 2007 I finally
got around to liberating the motor shown to the right.
The husked carcass is returned
to the same yard at over twice the value in scrap as 2 years had elapsed.
Fast-forward to 2008 (like right
now...) and the Cub-Cadet 582 is ready to start the conversion process.
Beyond stripping redundant cable
harnesses, replacing the steering linkage, some air in the tires and staring at
the chassis for hours on end it is still in the same state as when it arrived 4
years earlier.
This is what really brought this
project to the top of the list.
About $600 worth of lead,
delivered to theworkshop.ca at 0 (zero) cost. A condition of this most generous
of donations was anonymity.
Beyond being overwhelmingly
grateful of this cache of storage capacity, I feel an obligation to ensure that
these are put to a higher purpose than just gathering dust like the 582 has.
These types of cells turn-up occasionally
at surplus and liquidators such as Princess Auto and carry a hefty price tag.
The specs are 75Ah @ 12V per
battery.
75 X 12 = 900Wh times 4 = 3.6KWh
of total storage.
This is a substantial quantity
of energy... It's initial potential will simply be to provide motive force to
the Cub Cadet, which essentially will become a mobile energy station and storage
vehicle.
The device under test here is a
YI Yun YK42-4 48V/100Amp controller.
Some would say "hey, that's
the same type of controller used by Denise Ekhert on the world famous Mongoose
Dirt-Bike!"...
Correction! It is THE controller
used by Denise Ekhert... I was in the market for just such a controller and
opted to purchase Denise's controller off her as she'd moved onto a larger
motor/controller combo on her bike.
Beyond owning a small piece of
EV history, she gave me a very fair price and was very helpful when I was
setting-up the initial Dirt-E bike project.
With everything now known good
and working, the 50 year old Westinghouse is tested on the bench.
Even after years of usage and 2
years outside (at the scrap yard) the armature turns freely and smoothly on it's
bearings, the commutator and brushes are in good condition and have years of
life still on them.
As this is a series wound motor
(the stator coils are wired into series with the armature) it has fantastic
starting torque characteristics as the strength of the field rises in direct
proportion to the inertia of a locked rotor.
Similarly though, the series
wound configuration does not have a top speed or RPM/volt rating in the absence
of a significant load. This means that a motor with no load will keep spinning
faster and faster until it eventually self destructs due to centripetal force.
I mention this more so as a note
to my self that any operator of the Cub-E should be apprised of the damage that
revving the motor out of gear could entail.
But it does sound pretty cool as
it spins up to about 2000 RPM with less than a quarter of the throttle.
This motor is nearly identical
to the motor made by General Electric. It has 2 labels affixed to the housing,
one is a foil adhesive backed sticker that states 2HP @ 12V Max RPM 2300, Max
Current 56Amps.
While a smaller stamped tin tag
is bolted to the opposite side that simply rates it at 3 1/2HP @ 24V and 4HP @
36V (again consistent with the GE Motors). The 56Amp rating is actually closer
to 150 to 200Amps peak as I found over the course of the utility buggy project.
This is the foundation of my
rational to power the motor at 48V 100Amp Peak and typically 50Amps nominal.
This should equate to 3 1/4 to 6 1/2HP (if needed).
With the motor checked out 100%
a set of motor-mounts are tacked into place.
The critical factor was aligning
the motor to the driveshaft as directly as possible to minimize mechanical
losses before the transmission or wheels.
The mounts were fastened with
the MIG welder on low, and later dressed with 2 passes of the stick welder at
about 60Amps.
I'm still less than satisfied
with the execution of the mounts but for this phase of testing they will have to
do.
A short length of 1/8th"
walled 1" inner dia pipe is fixed to the output shaft of the motor while a
length of thin walled conduit couples the drive shaft to the motor with 3
(three) tack welds per end for now.
I didn't want to go nut's
fab'ing a heavy load bearing drive shaft till I knew that all was well on the
over-all project.
With the motor in place and
coupled to the transmission, I started to think about how the batteries would
get mounted. And the logical move was to strip the rear-end of the tractor down
to the frame.
The framing pictured above is a
mix of 1/8th", 1/4" and even a few lengths of 1/2" thick plate
and angle irons, Even the tow bar has been extended with the hope that the Cub-E
can move beyond just storing and moving electricity (though that in itself is as
much as I hope for).
Partially the motivation to
mount the batteries to the rear was to aid in the physical traction of the Cub-E
as the electric buggy is perpetually spinning it's
wheels unless it's loaded down quite heavily, which doesn't impact it's utility
too much though it is prone to get stuck more than I care for.
I opted to lay on a couple coats
of factory IH-Red paint at $12 or $13 a liter, while I returned the factory IH-White
to the shelf indignantly with a grunt to strike it from my account when the
salesman rang it in at $44 a quart.
This is an ideal conversion
candidate for a "Traction Engine" type application in that it has a
sold cast trans-axle assembly with 3 forward and 1 reverse gear, as opposed to
the more common Hydro-static drives that I fear would rob a lot of the juice in
the translation of motor power to motion of the tires.
The main power cables to the
motor are the longest runs and are #0/1 welding wire to keep electrical line
losses to a minimum.
To the right is a completed
connector and one about to be assembled. The copper tabs are made from
house-hold soft water pipe (that has been sanded inside out & soldered).
Hardware for this gauge of
material would be a few dollars a piece easily if not more.
The completed cable harness is
to the left...
The protective orange exterior
sheathing is from the Gorton
Mill acquired back in 2004.
Although it may not be obvious,
I did clean-up the motor terminals and the cable ends to ensure a solid
connection.
Anybody else would have just
paid the $100 bucks or so for an appropriate contactor to engage the battery
pack to the controller, but I knew I had a heavy double throw double post switch
out in the field (some where)...
Eventually I located this
stripped Yamaha Golf Cart Chassis (or at least it had a Yamaha motor in it)...
And it had a manual Forward/Reverse switch that presumably swapped the polarity
of the starter motor terminals.
It took longer to cut-back the
grass enough that I could remove the switch than to actually remove it.
There is only one post that is
badly pitted, while my intention is to have the switch throw the positive
terminal either to the controller or to the charger with at least 30 degrees of
dead power.
The buzzer (black disk with thin
black & red wires) is a "Bonus" as the Picox
Controller has had a majour revision that offers audio status tones (to be
added at a later date, note: link above is to the
original PicOx V1.02C controller Version 2.xx is due for release late 2008).
The switch is securely bolted to
the frame and is easily accessible for emergency shut down by the operator.
The wiring between the cells is
still the original test AWG#8 test leads used on the bench while the lines that
tie the batteries to the switch and on to the controller are AWG#4.
The greatest bottle-neck in the
wiring are the 8" to 10" lengths of AWG#12 off the factor Yi-Yun
controller. Of note is that these were definitely getting warm and demonstrably
more pliable after a 10 minute run at various speeds, gears and throttle
settings.
The Cub-E has met the defined
criteria of being able to move itself around the yard, as it's clearly out of
the shop now.
It definitely has
"traction" with the bulk of the weight behind the rear wheels, as it
can pop a wheelie dragging the tow-bar in all three forward gears.
This will be resolved in the
next installment that will see the addition of 2 (two) more batteries in similar
framing on the front, as well as a 1200Watt 24V Inverter.
This the first time that I've
ever seen the Cub-E with all of it's tin mounted... I almost threw out the side
panels a few times as originally the frame was going to be stretched to mount
the motor closer to the transmission and the 48V pack was going to be over the
front wheels.
Once all the metal work is done
on the front, all the tins and steel will be re-painted.
The YK42-4 controller will be
shelved and the "Brute Force xTender"
controller will be added as it already has heavier copper and can push the
motor to 150Amps at even higher voltages in the future.
Another issue that went
un-noticed until test day is that the brakes (internally in the transmission)
are locked-up, so the motor has to over-come the groaning screeches of their
resistance before any appreciable power is hitting the rear wheels. So I'm
in search of a service manual PDF to gain even greater efficiency of movement.