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Discussion Starter · #1 ·
I work in what we gently call the legacy energy industry. Needless to say some of my friends and family are not overly enthusiastic about EV's. Anyways just finished a mower conversion and since this site was a great resource I figured I would sign up.

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This is beverl-E

Looking at a low range classic pickup next :)
 

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Discussion Starter · #3 ·
Yes it takes a little more getting used to operating with both feet but I agree this setup seems much more efficient. With the ME setups the motor runs full bore constantly which to mee seems wastefull especially with dc motors being able to deleiver the needed torque for towing or driving at much lower RPM. The pedal also serves as my safety switch:) These old mowers are on the dirt cheap end of the scale which drove me this direction in the first place.
Hardest part? trainingmyself and the wife to slip the clutch or ease into the throttle so it still can be jumpy too. I adjusted the throttle so it can only go to about 80% which I found really smoothed things out. Early days though I only just finished it.

Happy to chat and share any details with you
 

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Discussion Starter · #5 · (Edited)
Sure thang

Started off like I said with the platform. An MTD 12.5 hp mower that had been stripped of its blown motor. 13bh662f516
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Then it was time for battery choice, I really wanted some EV cells but decided to keep it simple and go with 3x group 31, 90AH 12v deep cycles in series. I had planned to locate 1 in the rear but all 3 fit up front. Leaving room for a potential 48v upgrade. The two battery boxes are fabbed from 3/4 and 1/2" angle iron the upper battery box fits percectly in what was the gas tank area.
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Due to the pandemic (I guess) there were no ME motors to be had for less than a small fortune. I had seen people use forklift motors for various projects and when I came across a newly rebuilt 7" 36/48 dc series motor I snagged it for a good price. Two things I wish I had thought about before buying this motor * direction of rotation- this motor was built with only 2 external lugs so it was not easily reversed. * shaft size and connection type- the female 5/8 9t spline connection is common among gear pumps and nowhere else! Ended up being cheaper for me to snag a gear pump steal the shaft and grind the gear teeth off. Then because the od was 3/4 i used bronze 3/4" x 1" bushings to make up the difference. I welded a bearing to the motor mount and hung the shaft off of that at fisr but the e clips and snap rings kept letting go so i made a subframe and support the shaft from below(used some 1" aluminum pipe as a lower shaft since its not really load bearing).
The motor mount is just 1/4" plate chopped up into a big rectangle with an open middle.
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The controller is a chinese ripoff of a curtis 1205m. Didnt touch the programming just using a foot pedal throttle 0-5k that's compatible with the curtis unit.
There is a master switch that breaks the battery circut then also a keyed switch that closes a contactor. Once those two are turned on shes ready to go. Also in line is a 250A fuse and a shunt. The shunt feeds a Renogy 500A monitor which is has low alarms that can be set for voltage to prevent excessive rundown.
The electronics are mounted on a plexiglass platform suspended from the hood rails above the motor/ battery.
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