Re: (ET) E20 current draws update

["Tim" <rimmer59 hbci com>]

Mike,

I bought 3 of the following blades and used the original mower deck blade
bolts.

Oregon P/N 96-002  =  Dynamark 44252    Length 14-11/16"   Center hole -
3/8"

I installed them yesterday...they almost touch tip to tip and weigh a 
little
more than the old ones.
I also had to keep checking and reinstalling a couple times till the blade
tips would miss each
other.  They do have slightly more vibration...but the cut....oh the
cut...it is a huge improvement.
There is more suction to lift the blades of grass at the expense of drawing
only 4 more amps.
You would swear that the whole 42" width was cut by one blade.  Something
else, I have the
baffles and rear discharge.  I also noticed that I had to seal each baffled
area as to not allow air
to be redirected to any other place except toward the rear.  I maintain a
thick, lush, dark green
Kentucky Bluegrass lawn and now I am satisfied with my tractors cutting
performance.

Tim

----- Original Message ----- 
From: <metman glasgow-ky com>
To: <rimmer59 hbci com>
Sent: Thursday, September 16, 2004 12:08 AM
Subject: RE: (ET) E20 current draws update


Tim,

I meant to respond when you first mentioned the Oregon web site and
blades with 3/8" center holes.  Are you actually using blades with a
3/8" hole instead of 5/16"?  Are you still using the 5/16" bolt, or
have you drilled and re-tapped the shaft for a 3/8 thread?

I would suggest that you make some tests to determine if that induces
too much an out-of-balance condition.  I recently bought some Gator
blades from these folks and got ones that had a 5/8" center hole,
Then had some bushings made to reduce the 5/8" hole down to 5/16".

Mike Wallace


---- Original Message ----
From: rimmer59 hbci com
To: Elec-trak cosmos phy tufts edu
Subject: RE: (ET) E20 current draws update
Date: Wed, 15 Sep 2004 20:18:27 -0500

>Hi All,
>
>I have the large mowing deck motors.  I also have a PWM contolling
>the armature current and I switch in a power resistor (50 ohm) for
>field weakening when needed...kind of like a turbo switch.  With no
>field weakening the drive motor was receiving full pack voltage on
>the armature and field.  With field weakening the armature received
>full pack voltage and the field received approx. 7 to 8vdc
>(calculated).  The no load battery pack voltage measured 38.0vdc at
>the start of the test.  I did not measure the battery pack voltage
>sag with the different loads.
>
>Here is probably the biggest selection of 14" blades with 3/8" center
>holes I have found...
>http://www.oregonchain.com/OEP/oep_blades.htm
>
>Tim
>    From: Tim
>    To: Elec-trak cosmos phy tufts edu
>    Sent: Tuesday, September 07, 2004 5:33 PM
>    Subject: (ET) E20 current draws
>
>
>    I measured the current draws of various areas of my stationary
>E20 for future reference with a digital clamp-on ammeter.
>
>    Mowing Deck only; suspended in air with original high-lift blades
>= 25.5 Amps.
>
>    Main Drive Motor, current of armature and full field, with
>transmission in neutral = 11.60 Amps.
>    Field current alone = 2.00 Amps, Armature alone = 9.60 Amps.
>
>    Main Drive Motor, current of armature and weakened field, with
>transmission in neutral = 17.00 Amps.
>    Field current alone = 0.60 Amps, Armature alone = 16.40 Amps.
>
>    Headlights = 4.00 Amps
>
>    Mowing Deck Lift Motor = 16.00 No Load.  Max of 28.00 Amps to
>suspend deck level.  44.00 Amps just before stall.
>
>    Test conditions...Ambient = 70F.  Battery charge = Full.
>
>    Tim