Warning for anyone using trolley handle

[SimonWheels Unicycles]

WARNING... I fitted a handle to my unicycle (x7) and it's brilliant however one day after I fully charging my EU I immediately pushed my EU along with the power on, for about 10 mins as I was in a busy part of town and thought it best to not ride it until I got to a quiet part. That's when it all went horiblily wrong! I stepped on it and immediately as I started to move forward my EU powered down with no warning ejecting me violently face first onto the pavement. As it is winter here I was fully togged up so the padding cushioned the impact and I was ok. I tried to power the EU up after but it was not having it. The next day all was fine and my EU operated as if nothing had happened.

Conclusion, pushing the EU with the power on using an added handle charges the battery! As some EU's have overcharge protection circuitry pushing the device when fully charged is effectively overcharging the battery. Therefore:

ALWAYS MAKE SURE THAT YOU DONT FULLY CHARGE THE EU IF YOU INTEND TO PUSH IT BEFORE RIDING IT!

There is another posting relating to this giving advice on how to modify the circuitry to prevent this dangerous EU behaviour.

There is one positive thing to come from this though and that's if your battery is running low then you can walk for a bit pushing your EU and you will be charging it up at the same time. Also it may alleviate some peoples worries about battery drainage when using he handle when the unit is powered up, as the opposite happens.

Final though. I'm guessing that if the start of your journey is downhill the same applies but with more dire consequences!

[Cloud]

Wow...sorry to hear your wheel ejected you! I would have never thought that pushing the wheel charges the battery! I still find it hard ti believe - are you sure that overcharging was the cause of the accident? I always thought that when you push it, due to the leverage of the trolley, what you are really doing is tilting the wheel forward and then the gyros kick in and make the wheel motor propell its own weight....how much energy can you really deliver to the wheel by pushing it if you are not really pushing hard? With my wheel i hardly touch it and it goes due to the incline....this is so strange...

[Nevin@Tec-toyz.com]

5 minutes ago, Cloud said:

Wow...sorry to hear your wheel ejected you! I would have never thought that pushing the wheel charges the battery! I still find it hard ti believe - are you sure that overcharging was the cause of the accident? I always thought that when you push it, due to the leverage of the trolley, what you are really doing is tilting the wheel forward and then the gyros kick in and make the wheel motor propell its own weight....how much energy can you really deliver to the wheel by pushing it if you are not really pushing hard? With my wheel i hardly touch it and it goes due to the incline....this is so strange...

I would think the same as cloud. The only way I see it charging if you you were to push it on a decline. 

[Colestien]

   When I seen the title, Warning Trolley handle.  I was expecting a story about someone tangling up on a trolley handle when having to dismount. 

This is just a worry of mine because I tangled up in the safety strap when I was learning to ride (bad spill)

[Chuts]

I don't think overcharge was the main issue either.  If your EU overcharges it will start to beep to warn you of this.  My EU group here in Hong Kong went out fully charged and in an unplanned detour to the top of a mountain via bus we thought it would be great to ride down it.  All our EUs started to beep within minutes due to overcharge but none where ejected from their EUs.  On the day there where 8 of us, out that day where Gotway, KingSong, IPS and Airwheel.

[esaj]

I think this sounds more like the BMS cut the power due to too low voltage, the opposite of overcharge. The battery is next to useless in cold weather, and will die in about 15-20 minutes with something like -20C unless you have a battery heater, as the voltage drops FAST with cold battery... The voltage sag when you get going is very large, as a lot of torque (and thus, current) is required to get going from standstill.

[OliverH]

5 minutes ago, Chuts said:

I don't think overcharge was the main issue either.  If your EU overcharges it will start to beep to warn you of this.  My EU group here in Hong Kong went out fully charged and in an unplanned detour to the top of a mountain via bus we thought it would be great to ride down it.  All our EUs started to beep within minutes due to overcharge but none where ejected from their EUs.  On the day there where 8 of us, out that day where Gotway, KingSong, IPS and Airwheel.

Any measures done on any wheel? I'm interested in values.

[Nevin@Tec-toyz.com]

6 minutes ago, esaj said:

I think this sounds more like the BMS cut the power due to too low voltage, the opposite of overchge. The battery is next to useless in cold weather, and will die in about 15-20 minutes with something like -20C unless you have a battery heater, as the voltage drops FAST with cold battery... The voltage sag when you get going is very large, as a lot of torque (and thus, current) is required to get going from standstill.

Good point @esaj. Yes if your in cold weather, l would not push it unless u have a battery warmer or your EU has been on for a while. When it's near freezing, I notice the warnings come in eailer due to voltage drops. Take caution when riding near freezing temperatures.