three controllers, one throttle

[jeremybrowntattoos]

hello, i built a custom 3 motor trike and was wondering how to hook it all to one throttle? I know I need to find a common ground, I've tried that, I'm not sure if I did it right, I could run my back two motors and controllers with one throttle but every time I try to hook up the third motor I blow something. Can anybody help me out in the most laymen terms possible how I could run the signal wire and find a common ground to the third controller without frying another throttle, thank you in advance

 

[Chalo]

Use only one 5V (red) wire from one controller. So the first controller gets all three wires, and the second (etc.) gets only GND (black) and signal.

 

[amberwolf]

Are all of them running from the same battery? If so, they already have a common ground.

If not, then you need to connect all of the controllers' grounds (battery negatives) together to create a common ground.

But if any of the systems have any parts that connect to your frame electrically, such as one with a hubmotor with internal winding or phase wire damage that shorts to the stator laminations or the axle, and another has a grounded case bolted to the frame, then you'll be shorting across things by doing this, and failures will happen.


As long as the systems all have a common ground via battery negative, you simply connect 5v wire from *one* controller to the throttle's 5v wire (leave all the other 5v wires from controller throttle connectors unconnected), the same controller's ground wire to the throttle's ground wire, and the throttle signal wire from all controllers to the throttle's signal wire.


Keep in mind that you then have no way to modulate different wheels differently, which may complicate turning under power, depending on how your specific systems work and how you use them.

On my SB Cruiser trike I have both Phaserunner controllers fed from the Cycle Analyst's throttle output, so that I can use either my throttle or my PAS to control the system (almost always I just use pedal control of the speed, throttle is a backup or a "go button" when I cant get started pedalling). Each PR feeds one wheel on the back, and can be tuned to make the thrust the same on each side for the same throttle input.

It isn't "hard" to turn, but it would be easier on the systems and might turn tighter if I made a steering sensor that detected my steerer rotation and adjusted the throttle input to each controller proportionally.


When I used mismatched motors and untunable mismatched controllers, I'd have to make manual steering inputs to correct the unequal thrust, which changed depending on throttle input and speed I was at, just to go in a straight line.

 

[jeremybrowntattoos]

Are all of them running from the same battery? If so, they already have a common ground.

If not, then you need to connect all of the controllers' grounds (battery negatives) together to create a common ground.

But if any of the systems have any parts that connect to your frame electrically, such as one with a hubmotor with internal winding or phase wire damage that shorts to the stator laminations or the axle, and another has a grounded case bolted to the frame, then you'll be shorting across things by doing this, and failures will happen.


As long as the systems all have a common ground via battery negative, you simply connect 5v wire from *one* controller to the throttle's 5v wire (leave all the other 5v wires from controller throttle connectors unconnected), the same controller's ground wire to the throttle's ground wire, and the throttle signal wire from all controllers to the throttle's signal wire.


Keep in mind that you then have no way to modulate different wheels differently, which may complicate turning under power, depending on how your specific systems work and how you use them.

On my SB Cruiser trike I have both Phaserunner controllers fed from the Cycle Analyst's throttle output, so that I can use either my throttle or my PAS to control the system (almost always I just use pedal control of the speed, throttle is a backup or a "go button" when I cant get started pedalling). Each PR feeds one wheel on the back, and can be tuned to make the thrust the same on each side for the same throttle input.

It isn't "hard" to turn, but it would be easier on the systems and might turn tighter if I made a steering sensor that detected my steerer rotation and adjusted the throttle input to each controller proportionally.


When I used mismatched motors and untunable mismatched controllers, I'd have to make manual steering inputs to correct the unequal thrust, which changed depending on throttle input and speed I was at, just to go in a straight line.

thanks for the fast reply.. i do have the same motors and controllers hooked to one battery..so all theee of the thicker black ground battery wire from the controller should be hooked to the frame? then the signal wire will work? or do i hook all three of the smaller ground wire from the controllers throttle and connect to the main thicker battery wire? im sorry, i suck at wiring. im gonna re read tour reply lol.. i also tried to parallel my 2 48 batteries with an amazon 2 to 1 discharge connector but it zapped my smaller 48v battery. so now i have one battery powering 2 controllers with 1 throttle, and a separate battery piwering the front motor/controller.

 

[amberwolf]

thanks for the fast reply.. i do have the same motors and controllers hooked to one battery..so all theee of the thicker black ground battery wire from the controller should be hooked to the frame?

No, you don't want to wire anything to your frame. If you do, then any component or wiring failure that shorts something else to the frame can cause a system failure or a fire.

or do i hook all three of the smaller ground wire from the controllers throttle

Just wire it as previously stated, and it will then work.

If you're not sure, draw out all of your system's wiring as it actually is right now, on paper or in the computer in Paint or whatever, tracing out each individual wire to be sure of where it is actually connected, at what points in the system, and marking every single connnection point wherever it is.

Just draw it as it is laid out on the trike itself, so that you can also use it as a troubleshooting reference for later, as well as a starting point for changing the wiring right now. It's best if you can use colors for the drawing that are close enough to your actual wires that you can easily tell which are which within a cable, and also mark each wire with a label to tell you what it is for.

There are many good wiring diagrams you can find on the internet and this forum that you can use as examples of how to make yours--if you can't understand a diagram you find, don't do yours that way.


Once you have that, then you can post it here in this thread, and then we can mark changes on the diagram you can make to the wiring.

i also tried to parallel my 2 48 batteries with an amazon 2 to 1 discharge connector but it zapped my smaller 48v battery.

If they are not identical batteries at identical states of charge, directly connecting them together is likely to damage them.

If they are identical and at identical SoC, they'll be the same voltage and directly connecting them shouldn't cause a problem.

If they have BMS in them, then if they are not common-port types, you'll want to disconnect them from each other before charging. Then you also only parallel the discharge ports when riding, never the charge ports. If you're not sure, just do it that way; it's safer.

If you aren't sure if they're at the same SoC, measure their voltage with a multimeter before connecting, and if they are not identical, don't connect them together.

so now i have one battery powering 2 controllers with 1 throttle, and a separate battery piwering the front motor/controller.

I don't see a front motor on the trike, just rear motors.

 

[E-HP]

i also tried to parallel my 2 48 batteries with an amazon 2 to 1 discharge connector but it zapped my smaller 48v battery. so now i have one battery powering 2 controllers with 1 throttle, and a separate battery piwering the front motor/controller.

If you parallels the two batteries when they were at different voltage level, then you may have tripped the BMS on the zapped battery, rather than frying the pack. Does the zapped pack have a switch that may cycle the BMS when you turn it off and on? (In other words, the pack could still be good if the BMS resets).

You could connect the thick ground wires of all three packs to create the common ground, then per Chalo, connect the three wire throttle to one of the controllers, then run only the signal wire to the other two controllers.