Replacement controller

[Terry180]

I have a 36v 250w motor, the controller I’m replacing is a 36v 12a with a 36v 20a my question is will the controller cause problems with the motor

 

[gromike]

Most likely it won't cause a problem. Best if you buy a controller kit that has an included display. Displays tend to be specific to a particular controller (though some you can run without a display). Nice to get all the other bits to minimize the splices and soldering, and match the motor's connector to the controllers.
It's all pretty easy, as long as the bike isn't so proprietary, and the battery and controller don't need to handshake.

 

[Terry180]

Thanks for your reply and help, I’m merging two systems, the display and controller match each other, motor and battery from different system, all the cables match except changing the battery leads to a xt60, I was concern about the difference between the controllers , one being 36v 12a (original to the motor) and the replacement being 36v 20a

 

[PCeBiker]

It's possible that you could cook your motor with the extra power, but you may be able to turn down the power with the settings on your display.

If you can't adjust the power settings, hopefully you've got a Watt meter/Ahmeter/Power meter on your display so all you really have to do is keep an eye on it.

20 amps continuous could start overheating your wires, connectors, and motor until something burns or melts, so just keep an eye on things and you should be fine.

You should be able to reduce the power by simply turning down your PAS level, or just back off on the throttle.


I've got a 500 Watt motor, but I can give it quick blast of 1400 Watts for a few seconds without issue, but I can't go full throttle continuously.

 

[PCeBiker]

I’m merging two systems, the display and controller match each other, motor and battery from different system,

If both of your systems have a 36V 250 Watt motor, then you'll have no problem.
It's when you feed 500 Watts into a 250 Watt motor that things start heating up.

It may be the battery itself that was the limiting factor and could only deliver 12 amps reliably so they used a less powerful controller.

 

[Terry180]

Actually the controller/ display were used on a 500w rated motor since i only use the throttle from a stop briefly and normally ride in PAS 2, i’ll take the chance of burning up the motor, call it a science project

 

[PCeBiker]

Just pull over and put your hand on the motor to check it.
If it's too hot to touch, then it's too damn hot.

I bought a bunch of these and stuck one on my hub motor,..

It's got a better temperature range, because its for a coffee kettle not an aquarium.
Unless you're making fish soup.

https://a.aliexpress.com/_mNlhD4D

 

[harryS]

It's about the rider controlling the power, not the controller limit. You could probably smoke something with the original controller if you insisted.

Hill climbing while lugging the motor is what burns them up. If your display shows watts, don't let them get too high. Help out with the pedals.

 

[Terry180]

Thanks for your input, since I live in Florida I very seldom see hills, I also pedal all the time, going to use a S830 display which I understand has the capability of limiting the amps to the motor

 

[harryS]

Scariest hill I ever saw in Florida was crossing the Sanibel Island causeway bridge, Felt like my seat was above the guard rail and the water was ten stories down. Wind didn't help. Now this was before your hurricane wiped out the bike lanes, I wouldn't do it now.

 

[Terry180]

I usually ride the Pinellas Trail out of St Petersburg so it’s a flat surface except for a few bridges, makes for a nice relaxing ride.

 

[PCeBiker]

,.. going to use a S830 display which I understand has the capability of limiting the amps to the motor

I think I found it, but I couldn't find a setting that directly limits the maximum power,..

So, .. When Drive Mode is set to 0 (Power Drive) the gear assist drive decides the assist value, but your handlebars won't work, so you'll need to be going in a straight line, because you won't be able to steer.

In Drive Mode 1 (Electric Drive) your handlebars will work, but you won't have any power.

And in Drive Mode 2 (both Power Drive and Electric Drive) your "Electric Drive" doesn't work, and it looks like it won't even start, but I guess your handlebars still work so at least you can steer your ebike.

I'd suggest leaving your battery at home in Drive Mode 2 because it ain't gunna do you no good and it will just be extra weight to carry around.

P12 (Assist Power Intensity 0-5) won't do you no good either, because if you start with nothing, then you multiply it by 5, you still ain't got nuthin and you still may not be able to steer the ebike.


That seems like a Really Strange Way to design and set up an ebike but if it works, it works I guess??

(Personally, I'd just leave the damn ebike in the garage and buy a regular bicycle. They're cheaper, lighter, and Way Easier to pedal than a heavy ebike that has no power, that you can't steer.)

 

[Terry180]

You are absolutely correct for some reason I thought it had a setting to limit the output of the controller, the worst that could happen is to burn out the motor or wires but since it is being assembled with parts I had stitting around I’m not overly worried about it to much.