Electric Kart build version1.1 throttle help please.

[Alighee]

G'day from Western Australia. This is my first post in the forum so please go easy... I've really enjoyed and been inspired by the contents of everyone elses posts.
I'm currently working on a 24v kart for my 2 boys. They weigh 22 and 28kg. I have a general electric motor which i salvaged from an industrial tow kart which is being fed by a 275 amp curtis speed controller model number 1187-070, which i believe is the same as a 1205x?? This is attempt number 2. My first crack was using the same homemade chassis, a couple of 18ah sla batteries, 2 razor scooter 100w motors and an ebike speed controller. Which i soon discovered was dramatically underpowered. Any way getting to the point... the throttle i used for the ebike controller has 3 miscellaneous coloured wires but the curtis only has 2 inputs. Could i use this throttle still? Its one of the cheapest ones on ebay. Any help would be greatly appreciated. Cheers.

 

[itsid]

Old curtis controllers used a relatively bulky potbox for a throttle.
usually a 0-5k Ohm resistor setup
(google for "curtis pb6" to get the most common version of one)

if you want to make your own, get a 5k potentiometer with at least 5W (better 10Watts)
for durability, it also has one or two microswitches that need to be triggered IIRC.
but the exact layout of those throttles can be found online as well.

No.. most old controllers can not be signalled with a HE throttle (hall effect 0-5V three wire throttle)
more recent ones can.
IF and How is in the curtis documents.

Be sure that the motor you are using can be powered with the controller you have..
means: do not try to power a 48V motor, a BLDC, or a SepEx motor, just plain old brushed permanent Magnet motors.
SepEx (like you have) might work in some occasions,
but you'll need to series connect it properly it says "series wound" if that means it only has two terminals, give it a try, but be gentle, as soon as the controller gets warm, cut the power to avoid the controller getting hurt.


'sid

 

[Alighee]

Thanks sid. I'm kind of guessing that the controller is compatible with the motor, as i can't find any info from curtis on the 1187 model number but it shares all the same layout and terminals as the 1205x. I have followed the wiring diagram for the 1205x and it lines up with the 4 terminals (A1,A2,S1,S2) on the motor. Do the 4 terminals on the motor mean that it's series wound? Please excuse my ignorance this my first go... As far as making my own throttle pedal goes most of the pots I've looked at have a rotation of about 300degrees. I was thinking maybe a sliding rack and pinion setup? Has anyone made their own pot box and if so what mechanism did you use.? Thanks

 

[itsid]

it might very well be compatible..
I thought I'd remember the PM series being not..
but all references I can find call it compaitble with the M series which indeed is.
*shrugs*

Let's just say it is and see where that gets us

Yes a four terminal motor usually means seperate excitation
(which can be set up in a series configuration)
As you might have guessed.. A means armature and S stator

a slide pot isn't more convenient to use really,
a 300 degree pot is perfectly fine
as the axle shouldn't be laterally loaded anyways to not bend it, you will need
to offset the pedal pivot anyways, and then you can also just put two small plastic gears in to drive the pot (with a 4:1 gear ratio you have a 75° pedal movement 5:1 makes 60° etc.pp.)

But the M series allows for a 5V throttle signal (and if the two are indeed compatible.. yours should too)
and with that the hall effect pedals are back in the game.

I personally like the cable pull throttles best (since they allow for using the original pedals)
you can find one on https://electricscooterparts.com/throttlesstandard.html for example
(amongst many other ones... they can be had from china for ~10 bucks)

you can of course make such with a sliding rack and pinion using a pot as well if you like
with a 3d printer that should be pretty straight forward.

I made something alike the HE throttle last year
for very different reasons. (since the task at hand couldn't use a classic twist throttle)
it's fairly easy!
a good quality linear HE Sensor (I took SS495) and
a long neodymium magnet (I used a 20mm long rod N48(? would have to look it up...))

All you need is a way to move the magnet along the sensor (no need for physical contact)
and you're done...
5V power to the sensor and the signal line will go from 0 to ~4.7V
depending on the position of the magnet and thus it's magnetic field.
That easy!
since magnet and sensor needed to be seperated, my physical layout wouldn't help at all (especially since it also housed an attiny13 digitalizing the signal and sending it along)

'sid