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Is this MOSFET right for this voltage?

Hi, everybody. I have an electric unicycle (EUC) that has numerous issues reported by other owners on dedicated forums and on social media. The main issue with this unicycle is that it cuts out while riding it, which can led to severe accidents or even death (it has a max speed of 40mph). These machines are great fun, very practical and extraordinary compact, which made them very popular with niche riders. Unfortunately, from the beginning this form of transportation was plagued with problems: motor cut outs, instantaneous combustion of the batteries, poor water proofing, weak cases and other design, manufacturing and quality issues. Almost all are fabricated in China at this moment, with another producer in Korea, if I remember well.
To make a long story short, one of the producers that was known to make a little bit more safe and more reliable EUCs, InMotion, has started the production of a model(V12) that from the specs that were provided by the manufacturer promised to be of much better quality and with enticing speed and manoeuvrability. At this moment many received their V12s and alarmingly a lot of cut outs and accidents, resulting in bad injuries, started being reported. The reason for these failures are the burning MOSFETs: 12x Infineon IPP023N10N5 . The EUC has a 100.8V battery. The manufacturer, InMotion, claims that they received boards with bad quality MOSFETs from their controller board supplier. From what we read on this forum and other similar sites, many of the owners of this EUC, including myself, believe the MOSFETs were of underrated power for the voltage available on this unicycle. The battery is of 1750WH capacity and the motor is 2500W nominal, 5000W peak power. The only brake available on a EUC is regenerative brake. We had to become investigators of these problems ourselves, since we have little trust in what the manufacturer tells us. Would you please help me in clarifying this issue?
 
Sounds like a job for the importing authorities whomever they may be in your country.
That is if it was imported legally.
 
I live in UK. Technically in UK it is illegal to ride a scooter or EUC on a public land, unless it is one of the trial scooters approved by the government. With all that being said, there are so many scooters now that making them illegal makes no sense. It is a great feeling of resentment in the scooter and EUC community against police and government because of the multiple fines and of the PEVs confiscated, while “their” scooters are allowed and “legal”. The fact that they are consider “illegal” on public land also increases the distrust we have in addressing the institutions when we have issues with these PEVs, practically amplifying the issue and making a resolution unclear. Short, we don’t trust authorities on this issue.
 
It is 2:49 AM and I’m still on the internet searching info about MOSFETs. I have to go to sleep.
Did somebody said Parliament? Here I come, my queen!
 
That MOSFET has a 100V max rating so is not suitable for a 100.8V battery.
The MOSFET you use should have at least a 125V rating with the same or less on-resistance value.
 
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They are illegal in the UK for GOOD reason.
They are flippin’ dangerous!
Read the legal requirements to own and use one legally on public land.
The ones that can be bought or hired legally are within those requirements.

I have young kids riding ‘sur Ron’ 60 mph electric bikes on the roads with no helmets or lights.
It’s just a matter of time! And no doubt, the car driver will be blamed!.
Don’t get me wrong, I love them and would like one. But not on our roads.

Martin
 
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That MOSFET has a 100V max rating so is not suitable for a 100.8V battery.
The MOSFET you use should have at least a 125V rating with the same or less on-resistance value.
This matches pretty well what we found in other 100.8V EUC models, which also have at least 125V MOSFETs. It also matches what we read on speciality forums like this. Thank you.

They are illegal in the UK for GOOD reason.
They are flippin’ dangerous!
Read the legal requirements to own and use one legally on public land.
The ones that can be bought or hired legally are within those requirements.

I have young kids riding ‘sur Ron’ 60 mph electric bikes on the roads with no helmets or lights.
It’s just a matter of time! And no doubt, the car driver will be blamed!.
Don’t get me wrong, I love them and would like one. But not on our roads.

Martin
The SurRon is an electric bike not a EUC or a scooter, and electric bikes, limited to 30mph are legal. Scooters are not, except those approved for rent by the government. A road legal SurRon is available to purchase. An other version with higher speed is made only for tracks. It is not mandatory to wear a helmet in UK if you are a cyclist, but can be obviously dangerous, depending on your speed and type of road you are using.
 
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limited to 30mph are legal
I don’t know where you get your info.
They are limited to 15.5 mph and lower in certain places.
You have to have a valid driving licence to hire the trial scheme scooters of which, the operator pays insurance.
I will gladly eat my words if I’m wrong.

Martin
 
[QUOTE
I don’t know where you get your info.
They are limited to 15.5 mph and lower in certain places.
You have to have a valid driving licence to hire the trial scheme scooters of which, the operator pays insurance.
I will gladly eat my words if I’m wrong.

Martin
We are not discussing about electric bicycles. We are not allowed by low to drive EUCs on public roads. Period. With helmet or not. On bicycle path or not. With driving licence or not. With insurance or not.
 
We found the Infineon IPP041N12N3 G with 120V with lower power dissipation of 300W that has the same form factor. This is not the 125V ideal one, but way better than what is offered from factory. Even so we would have the issue of a new firmware release as the fall and rise time differ. To simply change the MOSFETs without also changing the firmware would be dangerous.
 
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