Cycle Analyst v3 ebrake on Pot wiring and config

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Willowfpv   10 µW

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Cycle Analyst v3 ebrake on Pot wiring and config

Post by Willowfpv » Sep 01 2018 1:13pm

I have a Kelly controller that supports regen braking via a 5v signal from a pot. I used a 5v thumb throttle on the left hand of my bars to act as the brake lever. I split the signal wire so that the signal goes to both the kelly controllers 5v analog regen pin and the CA v3 ebk pin. Regen braking is working but the CA is not acknowledging that the brake is applied. Should i just remove the ebrake wire from the CA and let the kelly deal with the braking? Or is there a way to get the CA to recognise when the brake is being pressed.

Many Thanks. Ben

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teklektik   10 GW

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Re: Cycle Analyst v3 ebrake on Pot wiring and config

Post by teklektik » Sep 01 2018 2:14pm

Willowfpv wrote:
Sep 01 2018 1:13pm
I have a Kelly controller that supports regen braking via a 5v signal from a pot. I used a 5v thumb throttle on the left hand of my bars to act as the brake lever. I split the signal wire so that the signal goes to both the kelly controllers 5v analog regen pin and the CA v3 ebk pin.

That's an interesting problem.
Typically you want the CA to know that you are braking so that it can cut motor power. This isn't as big a deal if you are using PassThru throttle, but if you are using one of the feedback versions (Current, Power, Speed) then the CA can start winding up the throttle signal trying to compensate for the braking and when you release the brakes there will be a surprise high throttle level waiting...

The other small glitch is that the CA won't do it's normal throttle ramping trick when you release the brake - which may or may not be good.

Ideally your regen 'throttle' would have a micro switch at ZERO that could be used to signal the CA, but I can't say I've ever seen such a thing on a thumb throttle, so your hookup looks reasonable this what is in hand (I'm guessing from the title the regen throttle is a pot).

You need to set EBk->SignalLvl = ActiveHigh so that the increased regen throttle voltage will tell the CA you are braking. I'm not exactly sure when the CA EBk input switches states but at some level of regen pot rotation the CA should 'see' the higher ebrake voltage and do the little icon dance on the main screen.

If the Kellys have a configurable voltage range for the regen input (like 1V-5V) you could stick a resistor, common silicon diode, or Schottky diode in series with the regen pot GND wire to bias the output up closer to the CA ebrake signal voltage so the CA would see it with less regen control deflection. Post back if the Kellys have such and adjustment and with the resistance of your pot/regen control and I can get you a resistor value to make that work.

Oh wait - we were talking about 12V braking setup in another thread - I think some extra details are needed here about your setup because of the whole 12V/5V controller/CA thing....
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Willowfpv   10 µW

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Re: Cycle Analyst v3 ebrake on Pot wiring and config

Post by Willowfpv » Sep 01 2018 3:09pm

Thanks, yes i decided to go with the 5v analog brake method as it seemed it would have more control over the braking force. I have the CA set for EBk->SignalLvl = ActiveHigh but the signal from the brake maxes out at about 4.2v. As the brake indicator does not appear on the screen then i assume the CA must need a higher voltage to trigger. Now that i checked the resistance on the (throttle) brake and it didnt change i see it must be a hall sensor?

https://www.ebay.co.uk/itm/Electric-Bic ... 2749.l2649

Voltage ranges between 2 and 4.2 when fully depressed.

The Kelly controller does have a setting to adjust the range of voltage that variable regen braking works within.

Thanks, Ben.

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teklektik   10 GW

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Re: Cycle Analyst v3 ebrake on Pot wiring and config

Post by teklektik » Sep 01 2018 3:53pm

Willowfpv wrote:
Sep 01 2018 3:09pm
Now that i checked the resistance on the (throttle) brake and it didnt change i see it must be a hall sensor?

https://www.ebay.co.uk/itm/Electric-Bic ... 2749.l2649

Voltage ranges between 2 and 4.2 when fully depressed.
The low voltage looks pretty high for a hall, but nothing looks right for a pot so I'm guessing hall - strange. The throttle looks nice, though. Is that voltage range in-circuit or with the throttle signal disconnected?
Willowfpv wrote:
Sep 01 2018 3:09pm
I have the CA set for EBk->SignalLvl = ActiveHigh but the signal from the brake maxes out at about 4.2v. As the brake indicator does not appear on the screen then i assume the CA must need a higher voltage to trigger.
This is a busy holiday weekend, but I'll test this soon and get some numbers for thresholds. I can hook up a similar hall throttle and see what might be needed to get it working. I'm surprised it doesn't work as you have it set up, but a little poking around should clear this up.
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Willowfpv   10 µW

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Re: Cycle Analyst v3 ebrake on Pot wiring and config

Post by Willowfpv » Sep 01 2018 4:02pm

Yes the voltage range is in-circuit. Dont go out of your way for a solution as braking still works for me in my current setup. When the kelly controller gets the signal it kills throttle regardless. Might be handy for people who use the other feedback throttle feedback versions as you mentioned. I thought maybe there would be a user selectable ebk voltage via the CA. e.g. set 2.3v for ebrake to activate.

Ben .

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izeman   10 GW

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Re: Cycle Analyst v3 ebrake on Pot wiring and config

Post by izeman » Jan 12 2019 7:09am

Willowfpv wrote:
Sep 01 2018 4:02pm
I thought maybe there would be a user selectable ebk voltage via the CA. e.g. set 2.3v for ebrake to activate.
This would be a highly welcome feature from my side as well. That way you can adjust for small imperfections of sensor <-> magnet location.

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