Is this normal?

[AzRadtrek]

Hi there,

I was wondering if what I see on my controller is normal.  I ride most of the time on power assist level two.  When the battery is fully charged (five bars) the watt output is usually 140+.  As the charge is used, the watt output changes.  At three bars remaining the output is about 12.  When it gets down to one bar the output is 82.  Is this what others experience as well? 

Thanks

[Rjbur007]

Interesting. It reads as if your wattage goes way down at 3 bars to 12 but then jumps back up at 1 bar into the 80's...

My experience has been as the battery reaches a certain level, I no longer get the power assist I was with a fresh batter as the voltage level is actually dropping... 

So I would say it's normal to see the amount of power or watts drop as your batteries level or voltage starts to drop.  For some time the power will seem flat with a fresh full battery, but eventually it will start till curve or drop off until you notice that with even 1-2 bars your working harder than before especially at 3-5 peddle assist.

I'd have to think that the 12 to 84 change your seeing is probably due to the terrain your riding.  I see my watt levels change quite a bit as I ride and I'm either gaining speed from a stop or heading on a slight uphill or down hill or into the wind or it's at by back...

In general, as your battery level drops, your voltage is dropping and the affects of the above can be seen even more in the wattage numbers....


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[Dan B]

I have not noticed this on my Rad Rover. I usually take it down to about 1-2 bars before fully charging. In PAS 2 and 4th gear I usually show about 130 to 135 watts no matter what the battery level indicates. I did go through the 3 step charge cycle that Rad recommends, which is supposed to kinda link all the batteries in the pac.  Sorry not much more help..

After further checking my above statement and keeping better track of my battery usage I  usually get around 140-145 watts shown when battery is fully charged and as the battery weakens I get a lesser watt reading of around 130-135 at about half charged and then drop below 100 when battery level is at about 1 bar.  Sorry for the misinformation. Thanks for your post, I have yet learned something else about the Rad..

[AzRadtrek]

Hi there,

I will see how it performs over time. I did not do the three step process before riding since it wasn't covered in the videos I watched or the manual. I did later see a rad video recommending the three step charge. Fortunately I was able to do that with my wife's bike that arrived three weeks later.


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[RadJohn]

Yes it is normal, as long are you really meant to type "At three bars remaining the output is about 120", not the 12 as originally posted.

It's quite understandable if you consider the basic electrical formula Volts X Amps = Watts.

The controllers on most Ebikes limit Amps based on PAS setting and/or throttle position.

Your "48 Volt" (nominal) battery is actually charged to about 54.6V fresh off the charger and the voltage drops through use until the low voltage protection circuit cuts off power at the bottom of one bar to prevent over discharge damage to the battery (probably at somewhere around 40 Volts).

So, as you ride, the circuitry in your display multiplies the Amps you are requesting by the Voltage the battery is currently capable of supplying to get the Watts it displays, and that will diminish as you ride.

Your numbers match those of my 2020 RadMini 4 almost exactly (again, if 120 is the correct three bar number) .   

[Dan B]

Great post Rad John.....