Re: (ET) I-5 foot pedal .vs. cruise control

[Charlie <medievalist gmail com>]

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
>>
>> _______________________________________________
>> Elec-trak mailing list
>> Elec-trak cosmos phy tufts edu
>> https://cosmos.phy.tufts.edu/mailman/listinfo.cgi/elec-trak
>>
>