Advise on cheap ebay controller for 72v qs205

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Ebuilt   1 W

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Advise on cheap ebay controller for 72v qs205

Post by Ebuilt » Mar 25 2020 11:59am

Can anyone with hands on experience advise on a cheap ebay controller for my qs205 running on a 72v system? I cannot afford anything nice, I dont care what waveform it runs, I dont need regen breaking, Im just wondering if youve had good luck with any of the <$50 controllers out there?
:bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt:

markz   100 GW

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Re: Advise on cheap ebay controller for 72v qs205

Post by markz » Mar 25 2020 2:03pm

EVFitting store which is Greentime on Aliexpress/Alibaba. Has SENSORED and UNSENSORED controllers.

HKSunwin on ebay might have some cheap SENSORED controllers.

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Dauntless   100 GW

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Re: Advise on cheap ebay controller for 72v qs205

Post by Dauntless » Mar 26 2020 12:28am

Wait a minute, WHICH 205? If your motor draws too hard on the controller it'll turn ugly real quick.

People used to like Greentime, recently some have said they went downhill. I'd like something close to 200amps sensorless for some 18 of those melons I've got laying around, but are they up to it anymore?

https://www.ebay.com/itm/GREENTIME-15-M ... 2842210917

https://www.ebay.com/itm/48-72V-1500W-E ... 2985062668
Any sufficiently advanced technology is INDISTINGUISHABLE FROM MAGIC!
- Arthur C. Clarke

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dogman dan   100 GW

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Re: Advise on cheap ebay controller for 72v qs205

Post by dogman dan » Mar 26 2020 6:08am

After wearing out a few real nice Lyens controllers, I economized and started using cheap ebay scooter controllers on my vintage 5304 motor. They don't last forever, but typically you get a year of high use riding out of one. Or not, when one died immediately I got it replaced by the vendor.

With the bargain stuff, just look for one with lots of length, so 18 cheap ass fets in it, vs just 12.

I like to look for self learning, which is becoming standard more and more.

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MadRhino   100 GW

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Re: Advise on cheap ebay controller for 72v qs205

Post by MadRhino » Mar 26 2020 10:33am

The QS205 V3 does not run with just any ebike controller. It is supposed to be run with a sine wave, and is known to fry most older infineon based (and clones) square wave controllers. I have fried 3 myself before finding one that does the job, and still running.

So ideally you choose one sine wave, for any sine wave controller will run the QS205.
If you want to run a cheap square wave controller, it is a gamble unless you can find the exact version of the board, that is usually not spec by sellers.
Make it fool-proof, and I will make a better fool.
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DogDipstick   1 kW

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Re: Advise on cheap ebay controller for 72v qs205

Post by DogDipstick » Mar 26 2020 11:26am

MadRhino wrote:
Mar 26 2020 10:33am
The QS205 V3 does not run with just any ebike controller. It is supposed to be run with a sine wave, and is known to fry most older infineon based (and clones) square wave controllers. I have fried 3 myself before finding one that does the job, and still running.

So ideally you choose one sine wave, for any sine wave controller will run the QS205.
If you want to run a cheap square wave controller, it is a gamble unless you can find the exact version of the board, that is usually not spec by sellers.
I have searched for concrete evidence of this, found none but your experiences Rhino. No doubt your experience is yours... but.. I want to know why..... If you could link I would appreciate. I run my motor ( even though not a v3)(same 36 mag config/pole) with a trap controller no prob...

but....
what about the square waves? For sure gona damage? You said one DID work for you... so what is it? That makes them blow? Doesnt QS sell a square wave? I thought the YKK they sold was square... and we all know MikeinPhilli loves those for his QS builds ( fellow ebikerbuilder with some experience with these hubs... here in Philla) ... I have seen many bikes built with them in this combo.

I want to know, I am about to hook one up.
Allota Watts @ 83.1v of raw QS power takes me everywhere on my Ironhorse DW link XC... :) Powered by Chevy. :D Broke 10 horses the other day. ( BTW; ...don't get hurt... :? )... (Currently building a battery datalogger.). :roll: Playin with (24) IRFB4115s now. :wink:

Ebuilt   1 W

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Re: Advise on cheap ebay controller for 72v qs205

Post by Ebuilt » Mar 26 2020 12:05pm

Thank you guys for the input, thats rad. Ill pull trigger on something today, I just cant afford to be frying $300-$500 controllers like i did my last one. One year out of a sub $100 is totally worth it.
:bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt:

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MadRhino   100 GW

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Re: Advise on cheap ebay controller for 72v qs205

Post by MadRhino » Mar 26 2020 12:37pm

DogDipstick wrote:
Mar 26 2020 11:26am

...
what about the square waves?
The one that I run has infineon eeb-3 board. It was by luck, after frying 3 of those that I had here on the shelves. I am not an expert in electronics. A friend did check them all and said that, those that I had fried were eeb-1 and eeb-2. He did build later with the same QS205H50v3 and found the same board as mine to run it first try. Then he had found the eeb-6 is also running it fine. The newer infineon is a sine wave in a different casing.

QS motor are selling many square wave controllers, but they spec this motor to be run with sine wave only. Maybe none of the square wave controllers that they have can run it.
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

Ebuilt   1 W

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Re: Advise on cheap ebay controller for 72v qs205

Post by Ebuilt » Mar 26 2020 2:57pm

:bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :bolt:

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