Throttle pulsing when light is plugged in to CA

t_tberg

100 W
Joined
Sep 23, 2015
Messages
204
Location
Pittsburgh, PA
I just bought a 20W led headlight that I've connected to the pack voltage via the CA's 5.5x2.1mm power plug. The light works fine, however, whenever the light is plugged in the throttle does't work properly; depressing the throttle completely only results in pluses of power. The problem goes away if the light is unplugged. I'm not sure if this is related but the CA tends to change to the next menu screen on its own sometimes. Has anyone had any problems like this while using the CA's power plug? I'm using the CA V2.3.
 
Well I guess I should delete this post, it turns out everything works fine if the light is plugged in before the CA turns on..
 
Actually disregard that last post, the problem still persists. Any ideas? The light is certainly messing the with the CA somehow, it switched to this screen on its own and read my max speed as 647 mph.IMG_0177-min.jpg

this is the worlds top American origiat for sure! Hilarious "product description" IMG_1434-min.jpg
 
t_tberg said:
I just bought a 20W led headlight that I've connected to the pack voltage via the CA's 5.5x2.1mm power plug.

...whenever the light is plugged in ...
  • ... depressing the throttle completely only results in pluses of power.
  • ... the CA tends to change to the next menu screen on its own...
  • ... read my max speed as 647 mph.
This is an electrical noise issue from the cheapo power supply on the light.

The light has some kind of built-in switching constant current supply so it can operate over that wide voltage range. The chopper is making noise spikes which are unfortunately being allowed to appear on the input power leads. These leads go through the CA so that the CA and light share the power leads back to the controller - this exposes the CA to the noise.

As you can see, this is manifest as bogus CA inputs - mystery pulses on the speedo input, mystery pulses on the button inputs, and mystery disruption of the throttle input. The CA is just seeing the noise on its inputs as valid signals and acting accordingly.

Not too many options here:
  • Get another light.
  • Hook the light up using a separate wire pair back to the battery.
  • Try to suppress the noise using a capacitor on the power leads between the light and CA. You might try caps in the range of 0.005uf to 0.1uf.
 
teklektik said:
[*]Try to suppress the noise using a capacitor on the power leads between the light and CA. You might try caps in the range of 0.005uf to 0.1uf.[/list]

I'd try several caps, different chemistries and capacities. An Electrolytic, AND a ceramic. Could be easily installed within the light. In parallel with it's power supply. i.e between its + and - wires.
 
I like the light and I'd also like to take advantage of the CA power supply to minimize the number of wires to the handlebars. I'll try some capacitors, I might have some at home. teklektik, you said to try between 0.005uf and 0.1uf, do I run any risk of destroying the CA if I get it wrong? It's as simple as wiring the a cap within those values between the power leads? Do the little ceramic capacitors have polarity?
 
Ceramics do not have polarity, electrolytics do.
A combination of both types helps cover different frequencies of noise (caused by the cheap switch mode power supply in the light).

edit: Like a mid sized ceramic and a tiny electrolytic.
Hope it works!
 
I have the same problem but without light or other device other than throttle, battery, speed sensor and shunt.

When speed goes aywire, the throlttle output shut down.
and I get 647km/h ou whatever impossible max speed.
 
Thanks for the tip on speed sensor !
It's funny I just repositionned it yesterday thinking that it could be that.
You just confirmed it :)
 
I know this is an older post but since I never invested in any small electrolytic caps and I've had no success finding tiny ones rated for over 16v in e-waste, I was wondering if anyone could give me some input on whether or not a ferrite bead (from a laptop charger) would suppress the noise that I'm experiencing when I plug a particular light into the CA. I've also found out that my controller that has the CA-DP is wired incorrectly as it reads the current that CA draws as negative (so that means I have to solder the CA shunt wires to the other side of the shunt?)
 
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