Cheapest source for kt controller and display

anon4

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May 9, 2017
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As the title suggests I am looking for the cheapest source of kt torque simulation controller and screen. So far pswpower comes out on top, either shipping is expensive or price too high elsewhere
 

Nealh

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Aug 7, 2014
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I use Aliexpress just because the buyer guarantee and service is better thru them then going direct, price wise no cheaper.

When you say ' Torque simulation ' that refers to a square wave controller for unsensored hubs so only 3 phase wires, no halls.
 

anon4

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May 9, 2017
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I use Aliexpress just because the buyer guarantee and service is better thru them then going direct, price wise no cheaper.

When you say ' Torque simulation ' that refers to a square wave controller for unsensored hubs so only 3 phase wires, no halls.
Ah, so do the sine wave ones still limit the power via current with the past settings because that's what I'm after
 

wheeliepete

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Feb 28, 2016
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do the sine wave ones still limit the power via current
Yes, you can adjust current with the C5 setting. From what's been said lately the new controllers now do this by % down to 50%, older ones had 5 amp adjustment, so a 20 amp can now be turned down to 10 if you so wish.
 

anon4

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May 9, 2017
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Yes, you can adjust current with the C5 setting. From what's been said lately the new controllers now do this by % down to 50%, older ones had 5 amp adjustment, so a 20 amp can now be turned down to 10 if you so wish.
I meant does the pedal assist settings also do this, so you get full speed on any level just reduced torque? That's what I heard somewhere and would like that sort of limiting as it's more practical than simply reducing speed to save battery
 

wheeliepete

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Feb 28, 2016
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you get full speed on any level just reduced torque
Yep, does that as well. quite a big jump from level 4-5, but full speed on all levels. I rode a bike a few weeks ago which was speed controlled, so to keep the motor running, you had to up the PAS level the faster you went, bloody horid and ate battery life, ripped out the controller and changed it for a KT 20 amp sine wave, set to 17 amps, owner could not believe it was his bike. He thinks he's getting almost twice the range now and a bigger grin.:)
 

anon4

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May 9, 2017
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Yep, does that as well. quite a big jump from level 4-5, but full speed on all levels. I rode a bike a few weeks ago which was speed controlled, so to keep the motor running, you had to up the PAS level the faster you went, bloody horid and ate battery life, ripped out the controller and changed it for a KT 20 amp sine wave, set to 17 amps, owner could not believe it was his bike. He thinks he's getting almost twice the range now and a bigger grin.:)
This is how my Carrera originally worked with the torque sensor setup range on eco was phenomenal given the battery size
 

Nealh

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Aug 7, 2014
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The KT sine wave controller P settings can be set up via all lcd, power can be speed or torque control.
Speed control tends to be crappy, torque gives more control and usually max speed in 2 -5 pas.
PAS 1 amps 13%
PAS 2 amps 20%
PAS 3 amps 33%
PAS 4 amps 50%
PAS 5 amps 100%

Throttle 100% in all pas levels.
 
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Davy

Finding my (electric) wheels
Apr 22, 2013
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As the title suggests I am looking for the cheapest source of kt torque simulation controller and screen. So far pswpower comes out on top, either shipping is expensive or price too high elsewhere
Can someone tell me how torque simulation works?
 

Nealh

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Can someone tell me how torque simulation works?
We call it current control, the Chinese call it torque simulation.
It is the supply of current to the drive motor. More current supplied gives more drive torque at the wheel or torque simulation.

A lot of cheaper kits use basic speed control for controllers , these often are 3 speed/ 3 levels of PAS. Each level gives max current at a set speed for PAS level, until BEMF reduces the current near the top end of the speed. Approx. L1 8mph , L2 12mph & L3 15.5mph, for most it means a one speed controller set to L3 to get near the cut off. Having max current leads to a big push (max acceleration_ at your back all the time and can catch some people off guard. Each PAS level is preset & will allow you to obtain max speed to the set cut off speed limit (this can be set above or below 15.5mph).

Other controllers esp the KT models use current control, most will use 5 levels of PAS. With current control each pas level gives a raise in supplied current in each level for a much nicer controlled take off from standstill, you select the level that gives the appropriate amount of power you are happier with as I listed in #8.

For most PAS 1 or 2 is plenty for flat terrain for minimal assist, if one goes out and feels tired or reaches an incline one selects a higher PAS level for more power then reduces it to save wasting the battery.

Woosh bikes use a similar current controller with Lishui and on some of there systems the end user can set the current % increments, so slightly different one could self select 20, 40, 60, 80 or 100% in each level.
 
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vfr400

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Jun 12, 2011
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For a DC motor, torque is proportional to current, so you control the torque with how much current you give the motor.

The cheapo controllers use speed control on the PAS, which gives maximum power when you set off regardless of the PAS setting. The torque simulation ones have adjustable current (5 levels), which gives a much more comfortable start up.
 

Darthpaul

Pedelecer
Mar 10, 2020
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The KT sine wave controller P settings can be set up via all lcd, power can be speed or torque control.
Speed control tends to be crappy, torque gives more control and usually max speed in 2 -5 pas.
PAS 1 amps 13%
PAS 2 amps 20%
PAS 3 amps 33%
PAS 4 amps 50%
PAS 5 amps 100%

Throttle 100% in all pas levels.
sorry the thread hijack, but is there a way to limit the throttle amps based on pas level? So if set to pas 3 we’d only get 33% of the amps on full throttle.
 

Nealh

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Aug 7, 2014
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sorry the thread hijack, but is there a way to limit the throttle amps based on pas level? So if set to pas 3 we’d only get 33% of the amps on full throttle.
No, throttle is all or nothing so 100%.
 

Scorpio

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Apr 13, 2020
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@Nealh there is a way but it took me a while to find it and I had to change 2 settings together, My throttle now matches my power level, not 100% all the time.

@Darthpaul My own notes are poor but might help:
C4 = 4 throttle / walk assist ? (set to P4=0, C4=4 for throttle max to match power level)
 

Nealh

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Aug 7, 2014
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Mine is older firmware I don't think I have a C4/4.
 
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