RE: (ET) novel motor use

[Larry Elie <lelie ford com>]

James, you wrote...

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From:   James Leuba 937-767-9976[SMTP:leuba cncrepair com]
Sent:   Monday, June 28, 1999 12:26 PM
Cc:     elec-trak cosmos5 phy tufts edu" "
Subject:        (ET) novel motor use

Larry,

I assume you used the propulsion motor?  What was the field current?

No, I didn't have a spare.  This was a DECK MOTOR.  One of the 'little' 
4.5" dia motors from the deck.  
The total current was 25-30 amps, the higher after the motor was having to 
draw from the well, you 
could here the RPM drop, but I didn't have a tach with me.  The thermal 
interlock worked fine; I am 
very sure I was easily exceeding the torque design limit of the motor.  I 
suspect even an E-8 motor 
or a snow-blower motor would have worked much better, I just didn't have 
one.

Larry Elie

Larry Elie wrote:
> 
> Scott, WHICH type of mower motor shell are you looking for?  Most of the 
> later ones are 4.5" dia, but
> one still needs to know which flange position (blade end of shell to 
> flange).  The "M" or mid-mount
> decks are at a different position than the front mounts.
> 
> On the side, I tried a novel ET application over the weekend.  My 3 HP, 
> 2" centrifugal Jacuzzi
> irrigation pump threw a rod.  The B&S engine was toast.  Yep, you 
> guessed it.  I put a normal
> mower motor (3000 RPM @ ? torque) in the place of the B&S engine.  I had 
> to ream the coupling,
> the ET's shaft is 3/4" and the B&S was 5/8", and put some new holes on 
> the bracket.  Yes, the
> motor did drive the pump.  I obviously exceed the torque rating by a 
> fair amount; the thermal
> cutout was letting it engage for about 5 minutes, than disengaged for 
> about 1 as it cooled.  It
> was pumping about 60 gal/minute (the B&S is rated 140 at 3500 RPM).  
> Unfortunately, the seal
> on the pump gave out after only about 6 hours (my fault, I didn't put 
> the check valve back because
> I was trying to reduce the restriction and every 5 minutes the thing had 
> to re-prime-- dry seals get
> HOT) from overheating.  Oh, yes, the charger by itself at 20-22 amps was 
> powering the pump, the
> motor draw was 25-30.  Lets see; 30 amps at 36 V is 1080 watts, and 760 
> would be 1 HP if the
> efficiency was perfect.  My duty cycle was about 83 % so my guess is the 
> motor is rated at about
> 1 HP.
> 
> Larry Elie
> 
> ----------
> From:   Scott[SMTP:Ke4cua bellsouth net]
> Sent:   Saturday, June 19, 1999 9:03 AM
> To:     elec-trak cosmos5 phy tufts edu
> Subject:        (ET) Schematics
> 
> I have a full set of schematics and a couple sales brochures, if anyone 
> is in need of a copy of a particular item let me know and I'll scan in a 
> copy and email it out.
>  I am in need of a motor case with magnets it tact of even just a magnet 
> for a mower motor would be great.
> 
> Scott
> Jax, Fl
> <<File: ATT00002.html>><<File: leuba.vcf>>