Tom Hudson via EV wrote:
I just found the information sheet from Simplicity on this machine and
the spec'd RPM for that motor is is 3700 +/- 50.
Sure would be a fun winter project. Sizing the motor is the big question
-- I see various conversions from gas HP to electric HP online, and I
want to be sure to provide enough power to match the gas engine's output.
Hi Tom,
I've converted a few pieces of yard equipment from IC to EV. Each case
is unique, but here are a few guidelines.
ICE's are generally rated by peak HP, while electric motors are usually
rated by continuous HP, which is lower. Depending on the type of
electric motor, it can deliver anywhere from 2x to 10x its rated HP.
When the load is intermittent, this means you can use a much smaller
electric motor.
I helped a friend convert his Wheel Horse garden tractor with an 8 HP
Kohler ICE to EV. We used a 1.5 HP 24vdc series motor. It actually had
*more* pulling power than the ICE, and no problem providing the average
amount of power needed for lawn mowing. We used two 12v group 27 deep
cycle lead-acid batteries. The controller was very simple; three
contactors, arranged to provide 12v with a series resistor (starting),
12v direct (slow), and 24v (fast).
Another friend converted a log splitter from ICE to electric. We used a
120vac induction PSC (Permanent Split Capacitor) motor from an air
compressor, and he simply plugged it in with an extension cord. The
motor ran a hydraulic pump, which had a small accumulator to handle the
high peak power needed to start splitting a big log. We also had a 15A
circuit breaker on the splitter as its on/off switch, as well as so an
overload would trip the local breaker rather than requiring a trip into
the basement to reset the main 20A breaker.
I converted a standard lawn mower with a 3 HP ICE into an electric
mower. I used a surplus 110vdc PM treadmill motor. I initially powered
it with an extension cord and bridge rectifier. Later, I replaced the
cord with a set of 60 surplus Gates 2v 2.5ah gel cells. Each cell was
about the size of a D-cell battery. The controller was nothing but an
on-off switch. I initially tried using a standard switch, but it failed
almost immediately from trying to switch DC. So I used the switch to
power a contactor, which in turn switches the motor.
I converted a classic ICE minibike to EV. It used a 2.5 HP 36v series DC
golf cart motor, and a small (Petrosonics brand) PWM motor controller.
The golf cart motor was actually too powerful; it was too easy to spin
the tire and lose control. A much smaller motor would have been better.
Lee
--
"#3 pencils and quadrille pads." -- Seymour Cray, when asked
what CAD tools he used to design the Cray I supercomputer
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
--
This email has been checked for viruses by Avast antivirus software.
www.avast.com
_______________________________________________
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
HELP: http://www.evdl.org/help/
