[slawking]

Way back when I was just a beginning member here I helped out someone who wanted a conversion with a tractor to electric. He needed a controller and wiring diagram to build his tractor. So I gave him a free Alltrax AXE4834 and give him a wiring diagram that I drew up in MS paint. So I suppose you guys are also looking for a wiring diagram. So here it is:

This circuit simply performs the AND function for safety as follows: the key switch, foot switch, seat switch, and throttle pot box lever switch must all be ON or HIGH in order for the lawn mower's traction motor to be active. The Key switch also engages the Negative side contactor. The reason a negative side contactor is used is so an extra safe guard is in place in case one of the contactors has a catastrophic failure such as welded contacts which makes it permanently ON. Also this actives the pre-charge circuit when the switch is turned on to avoid sparks being present when the user hooks up battery terminals to the batteries if this contactor was not present. Sparks at the batteries is not such a great idea so it also serves to reduce explosion hazards.

There is a warning that anyone who uses this wiring diagram should adhere to and that is the THE CONTROLLER MUST HAVE THE HIGH PEDDLE BEFORE POWER UP LOCK OUT ENABLED. FAILURE TO ENABLE THIS FEATURE IN THE CONTROLLER CAN RESULT IN SERIOUS INJURY OR DEATH IN WHERE THE USER CAN HAVE ALL SAFETY SWITCHES ACTIVE EXCEPT THE KEY SWITCH WHICH THE USER MAY CUT THE KEY SWITCH TO THE "ON" POSITION RESULTING IN INSTANT TAKE OFF OF THE LAWN MOWER WITHOUT WARNING.

As useful as this diagram is (and it is very useful), for Riding Lawnmower Purposes using a PERMANENT MAGNET SERIES MOTOR, a Controller is NOT desirable. I bought and ALLTRAX controller and found it totally NON-DESIREABLE. This is because of two major factors, 1) It is an unnecessary added expense (~$400), and 2) MOST IMPORTANTLY it forces the blades to run at VARYING SPEED (throttle dependent) which is HIGHLY UNDESIRABLE when mowing the lawn. A constant blade velocity when mowing the lawn is HIGHLY DESIRABLE when mowing the lawn, and both everyday Gas push mowers and riding lawnmower bear witness.

I am in fact planning to use the ALLTRAX controller for other purposes (as a tractor for hauling, etc), so the above diagram IS USEFUL for those kinds of applications.

Regards

Bob

 

[Bentzon]

Doesnt most modern lawnmowers have a hydrostatic transmission for the movement.
So all you would need a controller for is motor protection and low/high voltage cutoff.

 

[slawking]

Doesnt most modern lawnmowers have a hydrostatic transmission for the movement.
So all you would need a controller for is motor protection and low/high voltage cutoff.

My riding mower is an older double pulley belt design, these are still widely used today, and are some of the less expensive models out there. I would think that hydrostatic transmissions would still need to have a way to make sure that both the mower and blades move at a constant rate.

Do hydrostatic transmissions allow you to change gears?

If not, then a double contactor arrangement COULD be used in lieu of a controller for the HI/LOW voltage arrangement you suggest.

 

[Bentzon]

Its like a automatic gearbox with hydraulics instead of gears. They got belts from the motor to the hydrostatic transmission and to the blades. The blades are engaged by a magnetic clutch. So the input to the transmission and to the blades are locked by the pulleys. You can lower the rpm of the motor but it doesnt make much sense to do.

This is how its made on the one i got so my idea, if i ever get time to make it, was to just run a electric motor at full voltage for constant rpm all the time. Bolted to the original belt pulleys(where the ICE motor was) and let the OEM parts do the rest.
Probably not the most efficient solution but its pretty straight forward. I dont really see how you would run direct drive to both wheel and blades without getting poor cutting performance at low speeds. Expensive way to do it was to have one or two motors for the blades and one for the drive.

 

[Dennis]

As useful as this diagram is (and it is very useful), for Riding Lawnmower Purposes using a PERMANENT MAGNET SERIES MOTOR, a Controller is NOT desirable. I bought and ALLTRAX controller and found it totally NON-DESIREABLE. This is because of two major factors, 1) It is an unnecessary added expense (~$400), and 2) MOST IMPORTANTLY it forces the blades to run at VARYING SPEED (throttle dependent) which is HIGHLY UNDESIRABLE when mowing the lawn. A constant blade velocity when mowing the lawn is HIGHLY DESIRABLE when mowing the lawn, and both everyday Gas push mowers and riding lawnmower bear witness.

I am in fact planning to use the ALLTRAX controller for other purposes (as a tractor for hauling, etc), so the above diagram IS USEFUL for those kinds of applications.

Regards

Bob

Bob, the controller is only for the traction motor for speed control and current limit. Current limit is very important both to protect the motor from excessive current demand and to protect the batteries. If a large power resistor is cheaper then be all means build you a resistor based speed controller. It would be KISS design if you went that route, but do not expect it to be very efficient...

For the blades a better idea is to use separate electric motors connected to a type of "sacrifice" coupling that sheers keyways if the blades hit something hard so as not to damage the motors. Btw, there is no such thing as a PM series wound motor. A series wound motor has the armature circuit wired in series to the field circuit so it is always a 100% electromagnet type motor. If the motor uses permanent magnets for the field then it is a PM motor.

 

[slawking]

Thanks Dennis for the clarification of definition of series wound vs PM motors. I guess my point has less to do with the need for efficiency than for the need to maintain a constant mower speed and blade velocity. Adding a throttle to constantly adjust the motor RPM is not really conducive to that end (in my view).
As built, the mower runs for about 1 1/2 hour. In my part of the country the electricity used to recharge after that amount of time costs about the same as a pint of gasoline, so I guess it is efficient enough (for me at least). And its dead simple to maintain.

Regards,

Bob

 

[sjc]

Has anyone done a tractor conversion and used a power-takeoff (PTO)?

I'm looking at doing a conversion of a JD with a mower and snowblower. Is this any different than just driving the mower blades at constant speed?

sc
--

 

[partytrain]

Ok guys... after finding this site I would like to see if maybe I could get some help on a project. I see many of you have converted the riding mowers to electric and could probably give me some insight.
I am wanting to convert a craftsman tractor with hydostatic drive to electric... but not to cut grass to use an electric train for kids to ride on. I already have a great design using a craftsman tractor but would like an electric one to use inside malls during the cold months.

From what I have read I should use a 24v forklift motor with a controller. I was just wondering the run times I would get using 4 or more batteries... and also how to "connect" the motor to the drive train since some have done it.

My thought is using the belt system already there and attach the motor using the same pulley from the gas engine if possible.....

Any help would be appreciated!
Thanks!

 

[Jimdear2]

Ok guys... after finding this site I would like to see if maybe I could get some help on a project. I see many of you have converted the riding mowers to electric and could probably give me some insight.
I am wanting to convert a craftsman tractor with hydostatic drive to electric... but not to cut grass to use an electric train for kids to ride on. I already have a great design using a craftsman tractor but would like an electric one to use inside malls during the cold months.

From what I have read I should use a 24v forklift motor with a controller. I was just wondering the run times I would get using 4 or more batteries... and also how to "connect" the motor to the drive train since some have done it.

My thought is using the belt system already there and attach the motor using the same pulley from the gas engine if possible.....

Any help would be appreciated!
Thanks!

An indoor electric partytrain, a very nice idea for kiddy rides in a mall.

Here are some thoughts. Sorry about the length.

I think a hydrostatic is going to be difficult to drive because you will have two different power controls. You will need to add motor power then add load with the hydro then add motor power then more load. With a ICE the governor does this for you. You set the throttle to an RPM and the governor controls the throttle. A manual trans or direct drive may be a better choice.

With a hydro you will need to make sure you never have the electric motor under high power when you put the hydro lever into neutral or the motor will run away and maybe blow up.

If you go with a belt drive manual you can dispense with clutch and such. Once you get the primary reduction into the trans right you will find that the torque of the motor will be sufficient.

Remember when selecting gearing that electrics make the most power at low rpm up to about midway into there RPM range where ICE the power is more to the higher end of their range.

I would select a motor with power specifications similar to the D&D ES-15A for what you want. I can pull a 5 to 6 ton load on a skid plate at about 5 mph with 48 volts and 350 amps with my pulling tractor with a similar motor. There are a good selection of purpose built motors as well as a number of Lift Truck (Hi-Lo) motors out there.

Please look at the conversion I did shown earlier in the thread. I used a 6.7 inch, 24 - 36 volt motor on 48 volts and it works very well. I stress the Cub Cadet because it is built to last and will take more load then any garden tractor out there. As a note, 95% of the sucessful pulling garden tractors are built on Cub Cadet Transaxles, no matter what Sheet Metal they have on them. Also since the tractor is a shaft drive conversion is a snap. Another nice thing is the wheel bolt pattern is the same as 5 on 41/2 same as Ford and Chrysler passenger cars.

On brakes, NO garden tractor has brakes sufficient to stop a load like you are maybe thinking about and remember an electric motor has NO engine brakeing. The best you can do is get the mechanical disc brakes discs available on some of the hydro tractors and put a good hudraulic caliper and master cylinder on them. Maybe electric trailer brakes on some of the towed wagons? You sure don't want to run one of those poor kiddies down.

Batteries, you will want BIG deep cycle batteries for a day of running around the malls. The nice thing about the train idea is you can put batteries into the towed carts.

Your train idea has me thinking about next years town parade. I can get a few of those BIG FOOT yard wagons from Harbor Freight and build farm wagon flat beds on them and make a miniture hay ride to pull with my Cub Cadet puller.

So you will need basically the same things as a car conversion . . . PLUS EXTRAS.

1. A good motor, for this application some rated at 6 - 10 HP continious, RPM range around 3600, you should run at 48 volts (that is the highest "SAFE" voltage accepted by insurance underwriters) <bet you forgot about insurance>. No lower then 36 volts for efficiency.
2. Look at external cooling for the motor or be sure the motor is rated for the loads and RPM you are looking at.
3. What ever you need to connect the choice of motor to the choice of tractor transaxle
4. A good controller with a sufficient heat sink to not go into overtemp shutdown/cutback (big loads create heat).
5. Zero to 5k ohm Pot box or some other throttle device.
6. At least 1 good high amprage contactor (two are better-safer) with pre charge for the controller
7. Suffient fusing
8. Safety interlocks everywhere. Best is a wrist strap so no one can just jump on and go.
9. Mechanical disconnects fot the motor contactor in case you train comes unhooked.
10. Lots Of Batteries, without knowing the total weight, speed and other factors it will be hard to estimate what kind of watt hours you will need.
11. Depending on your frequency of use suffecient battery charge capacity. (Unsupervised battery chargers are expensive)

I know I've forgotten things so others please chime in

 

[partytrain]

Wow! Thanks For the quick response! Let me explain a little more detail and maybe it may help with the info you have given.....

1) The insurance is a snap as long as it is under 6mph and has an emergency stop and of course a fire extinguisher....

2) I understand the neutral position like you talked about.... And also the brakes (very Important) ... That is why I use the Hydrodrive on the one I have now....The Hydrodrive acts as a speed control and also a braking system..It gently slows the tractor as you decrease the speed and applies the brake in neutral....I still have the normal pedal brake also but dont use it except for a parking brake.... Just need to figure out the slow down the RPM of the motor at the same time so like you said the motor doesnt over REV...

3) According to the Specs the current Gas Engine on the Train it has a 3300 RPM & a MAX Torque of 9.76 ft/lbs - it is a 20hp motor

4) As far as the Batteries- I have plenty of room in the engine compartment and feel I could fit at least 2-4 Big Tractor Batteries or 6-8 deep cycles - Or can even build a Battery Rack once the Gas Engine is removed. My other thought was a "Battery Car" made to look like a coal car that was specificly for the Batteries.

5) My biggest concern is Safety first then Runtime - most events last 4 hours - as far as a mall, it would need to last 8hrs but my average ride is only 2.5 minutes - Speed isn't too big of a problem 3-5mph is great for the train now...

6) I found what looks like a modified mower called a BlueOx but it is $10,000 Way over my budget

Thanks again for the help...and maybe we can make this thing work and have it in every parade!

 

[Jimdear2]

2) I understand the neutral position like you talked about.... And also the brakes (very Important) ... That is why I use the Hydrodrive on the one I have now....The Hydrodrive acts as a speed control and also a braking system..It gently slows the tractor as you decrease the speed and applies the brake in neutral....I still have the normal pedal brake also but dont use it except for a parking brake.... Just need to figure out the slow down the RPM of the motor at the same time so like you said the motor doesnt over REV...

Partytrain,
I think ou will find that a hydro is going to be very dificult to use. I think we need someone who has done or tried a tractor with a hydro trans driven by an electric motor to chime in.

My feeling is that you would need some form of electronic RPM control that would maintain the motor at a specific RPM, like the governor on a gas (ICE) engine, I.E. whatever RPM that was set by the operator, to make a hydro work with an electric motor in a heavly loaded venu. Otherwise what you would be doing is stepping on a throttle adding load with the hydro lever or pedal till the motor starts to slow down, then adding more throttle and more hydro etc.etc.etc. Constant adjustment. The electronic control could be built I suppose, but I have no idea how or what it would cost.

Do not expect any form of motor braking like you get with a ICE gas engine when using electric motors, Unless you go for regeneative braking the motor just freewheels when power is cut. Regenerative braking is a whole different story and considerably more expensiive. Again it can be done with a sepex motor and controller, just bring money.

3) According to the Specs the current Gas Engine on the Train it has a 3300 RPM & a MAX Torque of 9.76 ft/lbs - it is a 20hp motor

If you go electric you will be pleasently supprised all of the torque is at the low end of the RPM range generally a 10 continous HP electric motor will have maximum torque in the range of 20 + ft lbs. amd it occures just where you need it for good pulling power. My pulling tractors never stall out they just go slower and slower until they loose traction. You will be pleasently supprised at the low end power.[/quote]

4) As far as the Batteries- Runtime Safety ect.

Before we get into batteries anf the other stuff, we need to know more about the train, approx. total max gross weight and what motor/controller/voltage you plan on using. I'm pretty bad at the math to figure that out but if you go to the battery forum, people there will help you. Same with the motor and controller forums.[/quote]

6) I found what looks like a modified mower called a BlueOx but it is $10,000 Way over my budget .

Are you maybe talking about the "Electric Ox" havent seen the BlueOx yet but I'll look

 

[gor]

mechanical trany - would be better 4 ev conversion - with hydro you stuck with speed and torque on what hydro set - if overspeed it (>3600)- hydrofluid will foam and cause cavitation;
- but ...we got what we've got (better than nothing : as they say: best one (for conversion) - free one) : )))) ; electrical part - most important, trany could be replaced later (or whole tractor - often people just giving ovey lanmower with bad engine ;


ariens makes el.mower with hydro http://www.ariens.com/products_lawn/l_amp/Pages/default.aspx
www.ampbyariens.com


p.s. blades speed also normally set considering 3600 rpm constant from engine, 27500-28500 feet per min. - blade tip speed; if faster -it can blow from under deck and instead of suction- just lay grass down (bad cut)


guys, can you tell any (approximate) numbers - on your mower - how much power goes to the blades (kW, amps) - how much time batteries would last with blades on/off etc)?
i know it hard to tell (all depends of terrain, conditions, how hard you push, etc - but at least some estimation, observation - your personal experience : )
thank you

 

[major]

Before we get into batteries anf the other stuff, we need to know more about the train, approx. total max gross weight and what motor/controller/voltage you plan on using.

Hey Jim and Party,

We had an e-tractor we used to pull a train. It would be 4 cars, each weighing about 1200-1500 lbs. Yes, like a 3 ton train. Trailers on pneumatic tires. Tractor used a 2 or 3 HP PM motor from an old floor sweeper. Had a 36V, 400A Curtis. Six 12V, 50 Ahr batteries in series/parallel. Darn thing even went up hill. Had a 3 spd forward w rev axle. Was belt drive. Later on changed to a chain drive. Was an old ElecTrak E8 (maybe E10).

I'd suggest you find a tractor to use without hydraulic drive. Just belt drive the motor to the transaxle. 36 volts should be fine. Longer run time needed; look at bigger batteries like for floor sweepers. 400A Curtis or maybe the 225A. Charger should not cost much. Golf cart charger or Minn Kota. Not hard to do or expensive.

Regards,

major

 

[aproldan]

i have done 3 tractors and one mini ride one and i will only use a mechanical tranny. the 3 tractors were used for pulling stuff and the mini is used for cutting grass.. you have more control on your speed and range.. when pulling heavy loads i would put it in 1st or 2nd gear.. when the kids just wanted to guff the back they would use 3rd-5th gear.. to me the mechanical tranny are more reliable.. and much easier to work with. and i use a controller on all my tractors.. and here may be a big shocker to most of you but i only use a 50amp controller... now my mini i use 2 motors one for the cutting deck and one for the drive.. the drive system uses a controller and the cutting deck uses an on/off switch.. works great.. here are 2 vids of my toys
http://www.youtube.com/watch?v=mvhqsWVk_Nk
http://www.youtube.com/watch?v=3Jga3nXYsIA

 

[Jimdear2]

Partytrain,

Since you have to use the hydro, I had a thought about a way of using it. I would like others with more experiance to chime in also on this idea. I might be all wet and totally wrong.

If you treat it like a manual, I mean find a "low gear" position for the hydro load lever that allows you to pull your load using the torque of the motor to get you up to a low speed then a "high gear" position for higher speeds.

Here is, how I would set it up

In the hydro neutral position I would use a micro switch to cut out the motor contactor. e.g. if you step on the throttle, nothing happens. I would use a controller like an Alltrax that has high pedal disable (this keeps the vehicle from moving forward if you should be steping on the throttle pedal when the main contactor closes)

Move the lever forward to a set low position, use a shift gate to lock the lever in that position. Chose a position so that when full motor power is applied the belt wont slip and the pump won't blow from the load. You can then use the throttle to get the train moving. Once the train is moving.

Move the lever forward to a set high position, use a shift gate to lock the lever in that position. you should be able to leave the lever there and use the throttle to drive around.

Reverse same thing

In other words, you would be driving the thing like a two speed maunmatic. if you do that I think you could simplify the driving and keep from blowing the pump

The other alternative is to get and swap in a manual trans from a similar garden tractor at a dismantler yard or look in the Surplus Center Catalog.

You don't need a clutch, just a direct drive, remember the motor stops when you let off the throttle.

I drive my electric all around in top (3RD) gear and pull in second or low. the only load control I need is the throttle.

 

[partytrain]

Jim - I do like your response.... I really think that setup would work with the hydro.... I am trying to find a used manual drive craftsman to try it on to see what would work better for my application.
I have been reading in all the forums about the motors and controllers....so many different kinds..
Which motor would you recommend trying first?
Also do you think the 4d or 8d batteries would give me the runtime I'm looking for...or another type?
Thanks for all the help guys... I'm just about ready to try the project in the next few weeks...

 

[Jimdear2]

Partytrain. one real good hint is see if ther is a branch of the EEA or some other EV organization in your area. You will find a lot of help there.

Jim - I do like your response.... I really think that setup would work with the hydro...

It might also blow up the pump. I am suggesting you try it only if you are unable to get a replacement manual trans.

I am trying to find a used manual drive craftsman to try it on to see what would work better for my application.

Check on the internet there are a number of commercial garden tractor dismantlers. Call one.

Look on Surplus Center's web site;

https://www.surpluscenter.com/sort.asp?UID=2156011114192894&catname=&byKeyword=yes&search=transaxle

They have a number of transaxles.

Check you local garden tractor shops for blown engine junkers.

Flea markets, swap meets, etc.[/quote]

I have been reading in all the forums about the motors and controllers....so many different kinds..
Which motor would you recommend trying first?

Stay away from golf cart motors that do not have a drive end bearing and shaft. You get stuck trying to make one . . . really nasty.
Continue your research. Read through the posts in the MOTOR forum by Jim Husted on selecting a lift truck motor and finding a good one. I sure wish I had before I bought my first motor. When you have an idea about the questions you need to ask and the specs you need to present I.E. weight, speed, etc. Post a question. The really experianced guys (unlike me) WILL help you find the best motor and controller. One that will be best suited for your needs and budget.

Same thing about controllers. Have some idea what you need to ask and go to the controller forum

Also do you think the 4d or 8d batteries would give me the runtime I'm looking for...or another type?

Same for the batteries. I'm afraid I don't know what the 4d and 8d terminology means. I can tell you that you will want deep cycle batteries for this project and like everything else, you get what you pay for.

Good luck and have fun. I'll pop in when I have something to contribute.

 

[partytrain]

Aproldan - Just watched the videos on the tractors you have built......
Have a few questions if you don't mind....
Which transaxel did you use? How did you mount the motor?
Also what kind of run time are you getting?
Could you post a pic on how you adapted the motor to work if you used the factory axel set up?

Thanks for your help!

 

[aproldan]

Aproldan - Just watched the videos on the tractors you have built......
Have a few questions if you don't mind....
Which transaxel did you use? How did you mount the motor?
Also what kind of run time are you getting?
Could you post a pic on how you adapted the motor to work if you used the factory axel set up?

Thanks for your help!

partytrain: the motor on the murray in mounted under the seat.. range depends on what gear i am using 1st gear(4mph) i get 45min. 5th gear (17mph) i get 25min.. but just incase your thinking that may not be much range it's perfect run time `for the kid and what i need it for... before i forget i am only using 12volt 12amp hr batteries.. i'm sure you will want to use much bigger ones..it uses a SPICER 5 SPEED(i removed the pulley and replaced it with a sprocket and chain.
here is my murray
the Montgomery Wards Tractor the motor is under the steer column and it used a peerless 5speed which is now in my mini...
and the green tractor in mounted where the I.C.E was the is the only one i left the pulley on... here is a closer look of my tractors

 

[gor]

partytrain: the motor on the murray in mounted under the seat.. range depends on what gear i am using 1st gear(4mph) i get 45min. 5th gear (17mph) i get 25min.. but just incase your thinking that may not be much range it's perfect run time `for the kid and what i need it for... before i forget i am only using 12volt 12amp hr batteries.. i'm sure you will want to use much bigger ones..it uses a SPICER 5 SPEED(i removed the pulley and replaced it with a sprocket and chain.
here is my murray
the Montgomery Wards Tractor the motor is under the steer column and it used a peerless 5speed which is now in my mini...
and the green tractor in mounted where the I.C.E was the is the only one i left the pulley on... here is a closer look of my tractors

hi, Aproldan
you still have a deck : )))) - can you tell hour range with blades on/off; (load on the blades, at least approximately)?
thank you