Kelly Controller 12V

General Discussion about large electric scooters and motorcycles and other things with no pedals.
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4r3st3r   1 mW

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Kelly Controller 12V

Post by 4r3st3r » Jun 27 2020 7:16am

Hi all,
Does anyone know if - rather than using a DC/DC converter - I can just use the 12V power source (number 11 on the diagram) from my Kelly Controller KLS7245N to power the lights / indicators etc on my bike? If so, how do I then ground that power source, using the standard ground on the controller (number 6 on the diagram)?
Thanks for your help in advance!

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amberwolf   100 GW

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Re: Kelly Controller 12V

Post by amberwolf » Jun 27 2020 7:22am

You must check with the controller manufacturer for the specs on the controller 12v output, and it's wiring diagram.

THen compare those to the current draw and wiring requiremetns for your 12v stuff.

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MACK   10 mW

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Re: Kelly Controller 12V

Post by MACK » Jun 27 2020 11:38am

Good question, I was wondering the same thing as I have the same controller to hook up. I've downloaded the manual but haven't gotten that far yet, (if the answer is even there). I'll speak up if I find out more!

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flippy   10 MW

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Re: Kelly Controller 12V

Post by flippy » Jun 27 2020 4:53pm

no, you can not. the 12v can only deliver about 100ma. its only for signal.

it says it very clearly in the manual.
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EddySPalm   100 W

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Re: Kelly Controller 12V

Post by EddySPalm » Jul 06 2020 3:08am

Hi,

I would also be reluctant to have my 12V system share the same ground as my high voltage (battery voltage) system.

Just purchase a decent isolated (very important!) DC-DC converter and you'll be fine. it is super simple to get up and running.

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MACK   10 mW

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Re: Kelly Controller 12V

Post by MACK » Jul 06 2020 2:41pm

Yes, I've been reading a lot of threads about using a 12V converter to run all the lights. It makes it (relatively) easy setting up wiring for all the lights, 12V out/ through switches/ to lights/ and back. I searched basic motorcycle wiring for bunches of schematics to look at and with only the lighting circuit (no engine) to deal with it's even easier. I'm also glad to start the lighting install before controller and motor since it's less cluttered and not full of big wires!

With regards to grounding, traditionally motorcycles would use the frame as a ground/return to the neg side on the battery, do people do the same with a DC converter on electric bikes? or would all return run through wires back to the converter?

My other question is, is the high voltage system ground contained within the battery/controller/motor circuit keeping it isolated from frame and rest of it, as long as all of those wires are insulated?


From what I think I'm understanding about regenerative brake with this Kelly controller (KLS7245N) is I can have the output from my 2 wire 12V brake signal split and send one to the brake lights and the other to the controller pin 25.

This is from the manual

brake sch.jpg
brake sch.jpg (138.58 KiB) Viewed 470 times
Since I'm using the brake light line from the converter for the input I would have to use the first diagram which shows using pin 20 (RTN) to return to the external supply. Is this correct and would it still keep the systems (hi/ low) appropriately separated?

Thanks

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amberwolf   100 GW

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Re: Kelly Controller 12V

Post by amberwolf » Jul 06 2020 3:43pm

MACK wrote:
Jul 06 2020 2:41pm
With regards to grounding, traditionally motorcycles would use the frame as a ground/return to the neg side on the battery, do people do the same with a DC converter on electric bikes? or would all return run through wires back to the converter?
There's a recent thread about that here:
viewtopic.php?f=30&t=106825&p=1565199&h ... e#p1565199
whcih while it's about the controller, it applies well enough to all grounding.

One piont not covered in it is bearings. If you have stuff on your bars or fork and you use frame as ground, you're runing current thru your bearings.
My other question is, is the high voltage system ground contained within the battery/controller/motor circuit keeping it isolated from frame and rest of it, as long as all of those wires are insulated?
Depends on your system. YOu'd ahve to check if it's all isolated, but typically it should be unless there is a fault (which is why there can be problems using frame as ground...when something faults and also connects itslef to the frame).

From what I think I'm understanding about regenerative brake with this Kelly controller (KLS7245N) is I can have the output from my 2 wire 12V brake signal split and send one to the brake lights and the other to the controller pin 25.
You can use a simple relay to isolate everything if you like, probably a DPST will work fine. There are threads about brake lights and switches that cover this; at least one or two I've posted in recently.

But if you have the option for proportional or analog regen, I highly recommedn taht, otherwise all you get is on/off braking, whcih means you don't want to set it too high or teh sudden jerk is discomfiting at best, and under the wrong conditions has the potential for cuasing you problems.

Then you can use a brake or clutch lever to control a COT (cable oeprated throttle) (there's trheads about that too) that then controls the braking amount. Most MC brake levers already have brake light switches in them, so no need to even connect that to any of the controller stuff at all.

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MACK   10 mW

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Re: Kelly Controller 12V

Post by MACK » Jul 08 2020 5:32pm

amberwolf wrote:
Jul 06 2020 3:43pm
There's a recent thread about that here:
viewtopic.php?f=30&t=106825&p=1565199&h ... e#p1565199
Yup, that exactly covers it, so no grounding to the frame for me. I kinda wondered being all electric, but I never considered the fact that the frame includes the axles and since the rear one is part of the motor...yeah, no.


amberwolf wrote:
Jul 06 2020 3:43pm
But if you have the option for proportional or analog regen, I highly recommend that, otherwise all you get is on/off braking,
Thanks, that's what wasn't clicking about the different brake inputs to the controller :? All my levers are spoken for (as currently configured), I did see your double pull ones but I'm now thinking about using a thumb throttle on the left (and rear) brake side so it could be regen and front brake, or I could add in rear disk as needed. Of course all the thumb throttles I've briefly looked at were meant for the right side, but it might be out there or I can deal with that.

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flippy   10 MW

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Re: Kelly Controller 12V

Post by flippy » Jul 11 2020 12:56pm

you can put a standard hall sensor on your existing brake lever and glue a magnet on the lever and set the controller to match so you regen before the pads touch the disk, that way you always use max regen when possible and only if you need more you can use the pads all on the same lever. lots of trucks a buses have the same basic function on their brake pedals but they use hydraulic brakes.
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