| You've gotten good advice. I can't comment on the operation of the I-5 but did something that may be useful. Have a typical E-12 but with an E-20 traction motor. Whatever motor used I always found mowing in L1 too slow and in D1 too fast. With help from list members I installed an E-15 double sheave pulley on the E-20 motor...mowing in L1 is just a bit slower but in D1 it is perfect. Cheers, Jack On Jun 5, 2012, at 2:58 PM, Charlie wrote: Great information, Brian, thanks! I do have a fast/slow switch. Now that I know what it actually does, I will experiment some more! Maybe D1 at slow will do the job. --Charlie On Tue, Jun 5, 2012 at 2:07 PM, Brian E. Haines < bhaines nycap rr com> wrote: Yup. Nail on the head.
Running the armature at full voltage and field at full voltage is the most
efficient use of power in a stock ET. If you lower the armature, you're
using the toaster to add resistance, lower power to the drive motor and
create heat. If you lower the field then the drive motor acts like a series
wound motor and more power is used...and greater speeds. (And generating
heat by using the resister on card 4)
Some tractors had a fast/slow cruise switch. Start the cruise in "slow
cruise" it would be full armature, full field. Flip the switch to "fast
cruise" and it would add in a resister to the field making it go faster (and
generate more heat).
With a stock I5 you're kind of stuck with just "cruise" a little too slow
and a little too fast.
If you're willing to do some modifications you could add a fast/slow cruise
switch. It will help a little.
If you willing to do a LOT of modification then you could put in an
electronic controller. No toaster, no card 4. Pretty much you use the
power you need and very little gets wasted. Also, you can wire in a cruise
button and a potentiometer and cruise at any speed you like. Wiring in a
cruise to an electronic controller is a pain though. WAAAAY easier to put
in a hand speed controller. Where ever you put it is how fast it goes. Less
wiring, less to go wrong, but some people love the foot pedal. (I'm not one
of them; )
Personally I hate the toaster and card 4. Converting energy to heat annoys
me unless I'm making grilled cheese. And anything that wastes my precious
power has to go.
B
On 6/5/2012 1:28 PM, Charlie wrote:
It was mentioned here a couple of weeks ago that the OEM cruise
control doesn't provide the top "field weakening" speeds, and that
seems to be true with my I-5. It actually slows down when I put the
cruise on.
I'm guessing that the motor runs cooler and more efficiently when it's
got the armature field weakened, but I'm remarkably uneducated
concerning electric motor control (and I know you guys aren't) so
please tell me if I'm being stupid.
If I'm in D1 cruise it's a little fast for good mowing speed. D1 on
the foot pedal is WAY too fast. L with cruise is too slow for me, and
L with the foot pedal all the way down is just right (said
Goldilocks).
But my size eleven gunboats are kind of large for the I-5's foot
pedal, and the spring seems awfully stiff. If I ride in
cruise-control, I won't get the most efficient battery use or the best
speed, but I have trouble maintaining constant pressure on the pedal
for an hour while I mow the open part of the field.
What do you guys think? Has anybody else had difficulty with this, or
am I just dealing with an unusually stiff spring?
--Charlie
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