72v ebike throttle ?

[jimmyhackers]

been a long time coming...

so far ive been runnign 72v through my 48v throttle with its crappy 3 stage lights....

needless to say its pants and i need one that properly represents my battery level....(this one show 3 bar no matter what)

ebay is useless for something this voltage out the box.

can you guys link me up please wiht a nice 72v twist throttle with a 5 stage(or more) led indicator and a key ignition....

fialing that can someone inform me on how to mod a 48v throttle (battery level display) to 72v please.

thanks in advance
jim

 

[Willow]

wowzers Jimbo...

 

[wesnewell]

Those idiot lights are worthless anyway. Just disconnect them and install one of these.
http://www.ebay.com/itm/RED-DC-Voltmeter-15-120V-Waterproof-Dust-proof-Shockproof-Panel-Meter-DC-24V-36V-/321405804645
If you must have the lights try Try a resistor to drop the voltage to the lights.
http://www.gtsparkplugs.com/Dropping_Resistor_Calc.html

 

[stevc]

Voltage indicator and throttle combo

http://www.aliexpress.com/item/E-bike-Accelerator-12V-84V-Battery-Volt-Indicator-Throttle-LED-Digital-Display-Gas-Handle-with-on/32425295520.html

 

[Gregory]

Nice, haven't seen those before.
Have to question their sales pitch though..and that looks like a right hand throttle to me.

this throttle is only can be used for left hand twist throttle, please pay more attention, thanks...

 

[amberwolf]

If you're willing to learn some electronics and do some hacking, you can open it up and change the resistors on the comparator circuits in there, so that it will work with the voltage range you are expecting from your battery.

I don't have any direct pointers to how to do it, but once you open it up, you'll probably see a couple of three-legged SMT parts in there, which are the comparators for the green and yellow LEDs, and some tiny brown chips with solder pads on each end, which are the resistors. You'd need to use a multimeter to trace out the wiring between parts, and draw out the circuits, to then compare to the datasheet for the comparators and any test circuits they may include in there. One you know what hte present values are, you can calculate what you need to change them to for your battery voltages.

 

[flangefrog]

Check the bottom of my post here: https://endless-sphere.com/forums/viewtopic.php?f=6&t=73036#p1102900

Your circuit will probably be almost identical to mine (the comparator on mine is a 324 Quad Comparator IC). If you need help with the spreadsheet let me know.

amberwolf - do you think the shunt regulator will be fine on 72V with no modifications?

 

[jimmyhackers]

thanks for the info

that throttle looks ideal...apart from it saying its only left hand :s ive messaged the supplier for a right hand one...waiting game begins.

did think about the voltage drop resistor......but i was unsure asto what milliamps i need to put into the equation.....as im guessing it changes depending on how many lighhts it wants to lighht up....

ill try the resitor with its "max" amp draw as its the easiest option.

thanks again for the help

jim

 

[amberwolf]

Check the bottom of my post here: https://endless-sphere.com/forums/viewtopic.php?f=6&t=73036#p1102900

Your circuit will probably be almost identical to mine (the comparator on mine is a 324 Quad Comparator IC). If you need help with the spreadsheet let me know.

Interesting; that's very different from the ones I have around here. I cant' find the post ATM but there is one in my DayGlo Avenger thread that shows the internals of at least one, maybe two, that use discrete components rather than a single IC for it (and is what my description above is based on).

amberwolf - do you think the shunt regulator will be fine on 72V with no modifications?

If it's a zener shunt, you might want to increase the series resistor to lower the current thru the zener, depending on what the zener's specs are.

 

[Voltron]

You can hook a 36v throttle to half the pack, and take the board out of a second broken one (I have a pile sitting around but maybe not everybody does) and wire that to the other half. I do that with my 72v pack, and I bulk charge it with 2 36v chargers, but I stopped worrying about the second half as I'm always checking the balance. Then you at least have your basic three light thing going..