Can I limit the power used by the q128c with the S-LCD3?

Davidwed

Just Joined
Nov 2, 2017
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england
Hi,

I have the Q128c 201rpm 36V motor along with a 36V battery and 20A sine wave controller from BMS. I'm looking to restrict the power to 250W but having read the manual can't quite see how to do it.

I tried lowering the C5 value (which i believe is the current) all the way to zero but the power its putting out is still around 600w when going up hill.

Can anyone help?

Cheers.
 
D

Deleted member 4366

Guest
It's dead simple. Set the controller to current control (torque simulation mode). Each level on the LCD will then be a different power. Level 1 will be about 100w, level 2 about 160w, etc.

Why do you want 250w? There's no legal limit on how much power you use.
 

Davidwed

Just Joined
Nov 2, 2017
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0
54
england
Great thanks d8veh, I had seen toque simulation but with the translation I wasnt too sure, I'll have a play with it. I thought the legal limit was 250w so was trying to make my bike closer to being road legal.
 

Benjahmin

Esteemed Pedelecer
Nov 10, 2014
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I thought the legal limit was 250w so was trying to make my bike closer to being road legal.
To be legal, the motor should be rated at 250W continuous and labelled as such. That is, it's capable of taking 250W over an extended period without overheating. The amount of power it actually consumes is dictated by the controller. In your case 20*36=720W maximum. Absolutely fine and not against the law - at present. Lower pas settings will deliver less power.
If a member of HM constabulary ever tests these parameters, please do let us all know, 'cos I'm sure we'll all be fasinated to know how he/she does it:D:p
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
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With the Q128 it is easy - look at the marking on the motor and if it says "500W" you are nicked...
 

harrys

Esteemed Pedelecer
Dec 1, 2016
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Have you tried C5=03, which the manual says is 50% of the current? I haven't installed my S12S controller yet, which is 20A too.
 

harrys

Esteemed Pedelecer
Dec 1, 2016
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S12S is normally 28 amps!
You're closer than me! Mine says 25A on the label. The thing is almost a foot long, just to hold all them MOSFET's. Well, that's rounding error. Maybe it's 7 inches, almost twice as long as the little PSWpower controller anyway. A third of the case is really empty too. I gotta use it one of these days.