[Squidlings]

Hi All,

I'm new to all this EV fun. Ive decided to build a basic cheap ev for fun.

DC forklift in an old rx8.

Controllers appear to be the expensive part.

I found this little thing on ebay and wondered if it'd do the job or melt and hiss at me every 10 miles?

https://www.ebay.co.uk/itm/500A-200V-72V-96V-144VDC-motor-speed-controller-PWM-current-limit-RS232-Arduino

Thanks for your time.

 

[GE11]

Yeah I have often wondered a lot about the experience with this controller as well!!!
I am hoping someone who has some mileage on this thing.
I don’t think it’s as robust as the open revolt controller though...
The open revolt controller is 500A continus while this this one is 500A intermittently

 

[Squidlings]

Strangely enough, I've just been reading up on the Open Revolt lads. I learned about them 10 minutes ago and I'm already hearing echo's of their name from yourself.

500a Continuous is really what I'm after TBH. Have some fun with that, however primarily I just need a basic car which can serve me 15 mile trips.

Is the open revolt an off the shelf controller now or still DIY?

Thanks for your reply.

 

[GE11]

The open revolt is a pretty mature product. When you buy it, from my understanding it comes in a kit that you put together.

For the controller on eBay, I have the 100V 500A version I might would sell if your interested. I have never used it before or even hooked it up..

 

[Eddie49]

The Hungarian controller on eBay that you linked to will run 350A continuous and 500A peak. I would guess that will equal or exceed the current requirements of a forklift motor.
However, it is a two-quadrant ( 2Q ) controller that has been specified for clockwise drive and regen. It is not reversible electrically ( then it would have to be a four-quadrant controller ), so you would need to provide a mechanical reverse gear - maybe you were going to retain the gearbox anyway.

 

[Duncan]

That controller looks pretty good - it looks like a development of the P&S Open Revolt

You don't need a gearbox to reverse but you do need a "Reversing Contactor"

!50v and 500 amps was pretty good in my car - but an RX8 is a bit heavier

 

[GE11]

Yes but has anyone put this thing to the test?? Has anyone used it and put mileage on it?

 

[Squidlings]

Cool, I wasn't expecting to many positive responses regarding the controller.

I'm so tempted to buy it but scared it's not quite up for the job. Wish they had a 1000A version.

I'm actually surprised how heavy the RX8 is, I was expecting it to be very light since it's small. Its almost impossible to push.

Thx for the offer to sell your 500a controller, but it's probably way off the power requirements I need. It'd probably suit an high powered ebike/motorbike

Yes, I'm planning to keep the transmission in the car, since I'm new, I won't be using the regen function unless it's super simple

I've started to watch electrical engineering videos on youtube so I can understand controller better.

For instance I now know a transistor is a switch and an amplifier, but I am unsure which the controllers use them for. I'm presuming a switch for sending pulses to the motor. Maybe both though???

I can't seem to find a place/link to purchase the open revolt model. I'd happily order one and put it together. I'm half decent at soldering. Made a few large LiPo packs from old laptop batteries for ebikes. So yes...car will be run on laptop cells MUHAHAHAHAHA Already have 1400x 18650's, probably need to double that figure.

Thanks all.

 

[Squidlings]

I do plan to overvolt the forklift motor.

Ive seen a youtube video on brush advancements which for unknown reasons to me, allows you to push more Volts and out out more performance from a fork lift.

https://www.youtube.com/watch?v=_deNnx-MppU

I don't understand why moving each brush forward 1cm allows you to push more power into it???

Im just trusting at the minute until I find the answers.

 

[Duncan]

Read the thread on using a forklift motor in the motors forum - it's long but good

You can overvolt and overcurrent a forklift motor

My Hitachi is 200 amps and 48v

So I'm feeding it 1200 amps and 340v

That could be a little excesssive and I did blow one up last year

I'm using the P & S IGBT controller - effectively his AC controller just simplifyed

 

[Squidlings]

I will read that thx. 1200a 340v is insane! I take it a brush advancement was required?

 

[Squidlings]

Im struggling to find the article u mentioned re "using a fork lift motor"

I cant seem to find a thread just random questions people have asked regarding their builds.

Is there a way u can direct me or link me up please?

 

[Duncan]

https://www.diyelectriccar.com/foru...ng-forklift-motor-and-choosing-good-7598.html

It's second from top in the electric motors section

 

[Batterypoweredtoad]

Read the thread on using a forklift motor in the motors forum - it's long but good

You can overvolt and overcurrent a forklift motor

My Hitachi is 200 amps and 48v

So I'm feeding it 1200 amps and 340v

That could be a little excesssive and I did blow one up last year

I'm using the P & S IGBT controller - effectively his AC controller just simplifyed

How many volts do you feed the motor? I know your pack is 340V but how much of that do you limit the motor to? I was under the impression that most non interpoled brushed motors top out in the sub 200V range.

 

[Duncan]

How many volts do you feed the motor? I know your pack is 340V but how much of that do you limit the motor to? I was under the impression that most non interpoled brushed motors top out in the sub 200V range.

No voltage limit -
At full throttle my motor sees full battery voltage at about 3500 rpm and above - my instruments are not operating very well at that regime ! - and I'm not looking at them
I suspect I'm sagging quite a lot

 

[Squidlings]

Thx for the link. Thats brilliant. I still cant find that thread manually. I need to play around to see what im doing wrong.

Thx

 

[dragonsgate]

I ran curtis 500 amp controller for years and when it finally gave out I gut a P&S and have been very happy with it.
A few days ago I took my wife for a little drive to a restaurant in my electric X19 through 15 miles of some nice turns and hills.
I hit it just right as there wasn't another car in sight either way so I wrung it out pretty good running in third gear and the amp gauge looked like it was glued on the 500 mark.
I would be leery of a $300 controller that was so far away.
That's my two cents.

 

[Squidlings]

Id be happy to buy a P&S but their online store is closed for maintenance. Im guessing theyve had their fun and moved onto other projects.

 

[GeorgeChapman]

Id be happy to buy a P&S but their online store is closed for maintenance. Im guessing theyve had their fun and moved onto other projects.

I may be corrected but I think that the P&S store is temporarily shut due to P&S having all their worldly belongings stolen during a house move from Seattle to Kansas City.
https://www.gofundme.com/f/help-this-family-moving-truck-was-stolen