120% on lyen program 3 speed switch.

[MFC Electrical]

I have a lyen 12fet controller with the USB link so I can program on my computer. Im using a 3 speed switch and you can set the speeds. I set speed 1 to 100% and 2 at 75% and 3 aT 50%. I noticed it gives you the choice for 120%. Has anyone tried this. How can you have more power then 100%. Dont want to over power or ruin anything but I figured 100% meant It was max. Any ideas?

[Philistine]

You can set the speed for 120% and it will give you extra speed (compared to 100%). My understanding is that it does remove some headroom that is left in there by mass manufacturers, so if you were running at the limits of your controller, then you might want to be careful, but unless you are running volts or current at the limits of your controller, you will be perfectly safe to run 120%. I program all my controllers to run on 120% throttle adds considerably to top speed.

[Ykick]

The difference between 100-120% speed setting on a DD motor is like going from 12S to 15S RC Lipo. I often forget to mention this when posting my top speed, motor wind, battery and wheel size.

[MFC Electrical]

OK so Lyen told me to keep the12 fet at 3500w or less. Amps x nominal volts. So I will set it to the 120% and do the math and keep it under 3500w. I will set it at 66.6v x 45 amps=2997 watts @ 120%. Does this sound OK

[MFC Electrical]

I sent the same originally posted question that I had about the 120% setting for the switch to Lyen and this was his answer. Thought it may be helpful to some.


"Here is the answer to your question on the 120% setting:
The controller forces the MOSFET transistors to switch on and off faster than usual. It will cause much more stress to the MOSFET. You so only consider to use it like a turbo charger for the engine. It is like having the turbo charger spinning at over 10K RPM. "Boosting" is continuously will have the potential to cause premature failure."

[cwah]

Anyone used 120% on a daily basis? Could ve quite convenient when you use a low voltage battery

[FastDemise]

I had it set 120% for a month on my 12s setup. I travel full throttle everywhere and it never seemed to hurt anything. When I went to 18s and 50a I went back to 100% throttle. I hear the setting makes it run a bit more inefficient than normal when boosted to 120%.

[Monstarr]

I used the 120% function for months last year, max 50A amp though @ 48V so ±2500W. I still use it nowadays when i occasionally use my electric scooter, max amp set on 80A and 50V so ±4000W (4100W max @ wattmeter). Doing this also for months now.

I have to put a sidenote to this, i dont drive long distance anymore, also dont drive very often because i live close to my work so i use my regular non-e bike all the time. This way i dont know if it will bother in the long run but for now everything is allright .

[amigafan2003]

Does 120% speed setting not work on geared motors? I set it on my lyen and it didn't increase my top speed (Tongxin hub, no halls).

[cwah]

I haven't done that yet because I'm afraid of burning the fets of my controller. But I may try that to increase the max speed.

[ohzee]

I use a 3 speed switch on my Mac 8T with no issues.. 120% gives a big improvement.

I also run a Lyen 12 fet at 24S 60 Amps hitting 5k peaks.. done this for about 4 months now with no issues.. stock controller no mods.

I know I am at the breaking point - I also have 2 backup 12 fets for when I hit it.

[cwah]

Is it much less efficient or not? Maybe we can use them daily without problem? And if efficiency loss is negligible it could even be better

[Kingfish]

Overclocking the Controller:
I have programmed my controllers to 115% and 120%; it's about the same result. You set this value in the programming app, save it, flash the controller, then test. Bug: When I reopen the app there is a quirky bug that resets the value back to 100% and/or ignores it.

The overclock works very well. For my road trips (@ 63V), I had my three settings as:

• ~52-55% <= 20 mph guaranteed (both FWD and 2WD). I used this setting like… twice ever.
• 85% <= 35 mph (2WD).
• 115-120% > 40 mph, and sucks a lot of power! (2WD) I used this setting to get into the 40 mph Club

Of course the other factor that is missing is the Phase and Battery Current; I limit my wheels to 2 hp each (~1500W)

The faster you go - the more power it will take. Overclocking the controller doesn’t buy efficiency, but it does squeeze more fun out of a stock setup!

Cheers, KF

[cwah]

Is it because you overclock the controller that it's less efficient, or is it because of the speed?

I'm wondering if the power usage would be much different between an "overclocked" and a "standard higher voltage" setup?

[Kingfish]

Is it because you overclock the controller that it's less efficient, or is it because of the speed?

I'm wondering if the power usage would be much different between an "overclocked" and a "standard higher voltage" setup?

Speed. There's a long thread that discusses the effects of overclocking very well, though for the life of me I don't have the link. Essentailly, Setting to 100 or 110% is fine, although the jury is out for 115 and 120%. The controller ignores or won't flash if the value is set higher.

I have my system balanced at 85% so that switching between high and low is a significant change. It's fricken awesome though to go 40 mph in the speed zone and able to keep up with traffic. I just like the white-eyed look that people get when they see you're still pedaling!

Power usage: That sounds like a perfect subject to explore
I suspect the output will be similar. It was discovered that WOT is not really 100%, and overclocking is supposed to get us closer to pure open, but instead we have phase shifting (I believe I have that right) and it's this shifting that allows the motor to perform better, like advancing the spark during acceleration.

~KF

[ZOMGVTEK]

My bike takes a HUGE efficiency hit when going from 100-121% (Using XPD). I get about 6 MPH more, and it takes over 1kW more.

Obviously the speed has quite a bit to do with it, but the controller appears to be substantially less efficient as well. I wouldn't recommend running around above 100% 24/7, but it should be fine for short bursts.

[Jeremy Harris]

It's really wrong to refer to "120%", even though Keywin's (and hence Lyen's) programming utility wrongly uses this description. You can never get higher than 100% duty cycle, no matter what you do, as this is a physical limit - the controller cannot increase the battery voltage. When a controller reaches 100% duty cycle it effectively switches from pulse width modulating the input voltage to drive the motor, to having the whole battery voltage switched to each phase in turn. This is often referred to as block commutation.

When you select the "120%" setting on a Xiechang controller (be it one supplied by Lyen or one from one of the other suppliers of these units) then what you're doing is changing the throttle setting at which the controller switches from PWM control of the motor to full-on block commutation. In some cases (maybe those where the motor never normally runs fast enough to reach 100% duty cycle when under load) setting 120% may give a bit more power, but that will come with a significant efficiency hit. In other cases using the 120% setting won't give any increase in power, just an increase in motor current and sometimes a bit more motor noise.