Re: 120 V AC to 120 DC Lawn Mower Conversion. CORDLESS !!

[Lee Hart <leeahart@earthlink.net>]

Steven S. Lough wrote:
> 120 DC will run a 120 AC brush type lawn mower just fine. The problem
> is getting  up to or near 120 DC with small lead acid batteries.

Exactly. I converted my corded electric lawn mower to cordless with 15
packs of 8v 2.5ah Gates gel cells (purchased surplus for $5 each). The
first problem was having to buy about 20 of them to get 15 with decent
amp-hr capacity.

Second problem is (as you know) that the stock 120vac switch will NOT
switch 120vdc! The switch operated a relay (240vac coil with series
resistor to draw same current on 120vdc) that switched motor power
on/off.

Third problem is charging. I just used a bridge rectifier and a long
extension cord (John Wayland would like it :-)

It worked fine for my small yard. Running current with this mower was
5-10 amps, and I had enough power to mow my little yard.

I used it this way for 2 years. But one by one, the batteries failed. No
charge controller! I equalized them manually when I got around to it a
couple times a year.

When I moved to Minnesota, my yard was larger and hilly, so I converted
it back to a corded mower (which I'm still using today).
-- 
Lee A. Hart                     Ring the bells that you can ring
4209 France Ave. N.             Forget the perfect offering
Robbinsdale, MN 55422 USA       There is a crack in everything
phone (612) 533-3226            That's how the light gets in
leeahart@earthlink.net                  Leonard Cohen