This forum is in read-only mode. Please continue to browse, but replies are disabled for now. Why?

Wire two speed controllers to one throttle and one battery pack.

Common electric scooter, bike, and go kart speed controllers use a 1-4 Volt DC input signal to control the motors speed. It does not matter where the input signal comes from as long as it is a 1-4 Volt signal. Most throttles have a 0.8-4.3 Volt output signal just to be on the safe side.

Wiring a single throttle to work with two speed controllers is a very simple and straightforward procedure. All you need to do is wire the throttles + 5V DC input power wire (red) and ground wire (black) to one speed controller, and then wire the throttles output signal (usually green or white) to both controllers. This method will also work with more than two speed controllers.

One battery pack can supply two controllers. The battery charger can either connect directly to the battery pack or it can connect to one of the controllers if the controller has a 'charger in' connector. Here are two illustrations showing how to wire everything together.

Charger connected directly to battery pack:

Charger connected to one of the controllers.


Please let me know if you have any questions.

4 people like this idea
Thank you for posting the wiring diagram. I was able to wire my throttle signal by making a Y harness for the signal wire as you described and my system runs! This is on a light weight ebike. But I had a bit of a struggle at first and I was wondering if you have a solution? The second controller I used came with a throttle that has a Cut/Kill button and a battery meter light. I didn't want to use the throttle with all that(just too big and bulky). So I used another one, but the second controller won't run without the the connection to those leads from the first bulky throttle. Once the battery indicator light are on the controllers work great driving both my wheels. My temporary solution is lame as I just keep those leads plugged in and put the throttle in the bag with everything. In the attached image I show the blue signal line from my throttle and the controller leads connected but the throttle is disconnected, which will run but I don't want to carry that throttle around. Thank you for any help!
(1.09 MB)
The brown and yellow wires are for the power switch that connects to the controller. The power switch is a required connection for the controller because it is needed to turn the controller on, and needed to turn the controller off when the scooter is not being used so the batteries do not get drained.

Unless there is already a power switch between the battery pack and controller then the controller's brown and yellow wires will need to be connected to a power switch. If there is a power switch between the battery pack and controller then the brown and yellow wires can be bridged together so they permanently make contact with each other.
Thank you for identifying those wires, I connected them, as I have a power switch installed at the battery. Systems up and running!
Hi friends. Its is good my project? Help my please.
Hi Tomas, your project looks good to me. With all wheel drive it will drive through sand and mud like nobodies business. I would make sure you have some pretty beefy brakes on it though with all of that power.

hi. friends i need battery 2500w or 5000w ? 

Hi Tomas, batteries are rated in Volts, Amp hours, continuous Amps, maximum Amps, plus other various specifications instead of in Watts like motors and controllers are. With a Lithium battery pack one of the most important specifications is the continuous Amp load rating. If your scooter will have two 96 Volt 2500 Watt controllers then these controllers will be able to continuously draw 52 Amps from the battery pack. So a 96 Volt Lithium battery pack with a 52 Amp continuous load rating would be needed.

thank you.

Hi, running two motors off two controller as you showed in the diagram above, works great(thank you). My next question is, can I run two batteries with each controller having its own battery. Seems like it would work but am I missing something? The signal wire only carries the signal voltage so a two battery system shouldn't effect the motor timing. I'm over my amp limit on my BMS which is rated at 20 amps. I'm pulling around 23 amps on my battery so the BMS kicks in at times. It's hard to find a 40 amp BMS, cost more etc. so I'm thinking of running two 15 or 20 amp rated batteries which would also give me really great capacity.
Yes you can run two batteries with each controller having its own separate battery. Using two batteries will not effect the operation of the single throttle. The throttle will work normally with two batteries, just as it does with a single battery.
Ok so much for my common sense. I could not get this to work. My single battery drives both controllers very well, but when I hook up a separate battery for each controller my system only responds from the first controller. Each of the two batteries can drive the system but for some reason I can not power each controller seperately. I thought to myself that the signal from the throttle is being cut off. Signal wire is a single wire so I'm not sure how to test it to see if it's sending a signal to the second controller. I assume it isn't so the second controller isn't responding. My volt meter does pick up anything when powering but I'm not sure I'm testing it as even when both motors work I cant see the signal on my volt meter. Thank you for any help on this.
I believe that this problem could be solved by bridging the negative wires of both battery packs together. Here is the drawing.


This way the throttle which is getting its power from only one of the battery packs will be grounded to both battery packs which should allow it to pass its output signal Voltage to both controllers.

Please let us know how it goes.
Yes, you are right! That was it, the ground needs to be common for the controller to see the primary throttle signal. Great support here at ESP!

Hello everyone, some time ago I started experimenting with my E300 razor :)

first, the throttle with overvolted kit to 36v, and lithium batteries, the improvement was notorious, but it was still not fast enough for me (hehe) so I got a 36v 800w motor and a controller for that motor.

a couple of weeks ago, and after seeing that it had already been experienced on the internet, I decided to mount more batteries, a second motor and controller (36v 800W), try to connect both as figure the scheme but I can not make both ... some kind of help ?? Thank you

If you have the negative wires of the two battery packs bridged together and it is still not working then we recommend plugging the throttle into each controller one at a time to verify that both controllers are working. If both controllers are working individually but only one controller operates when a single throttle is wired to both of them then the problem could be with the wiring or connectors between the first and second controller.

Login or Signup to post a comment