I can understand that you are frustrated about two blown up VESCs. I talked about your issue with Benjamin, and he is also convinced that the switch inside the BMS did cut out for a second.
A higher rated VESC would have blown up just the same way. If the BMS separates the battery from the VESC, the chance for device survival is minimal.
I use this 18S bms and its working great so far:
https://www.lithiumbatterypcb.com/product/20s-lithium-smart-bluetooth-battery-bms-with-50a-constant-current/
Since it’s a 18S-34S BMS shouldn’t it be used at 34S to get a better efficiency, regarding to Frank’s theory?
Yeah same one on order but 20s variant. I have the programming tool so I can change them to 18s if needed
It does not matter. BMSs work an a cell basis so a 34S BMS has more mosfets than an 18s BMS, that is all.
Yeah I am very frustrated! The service you offer now at this moment is very disappointed. The price it cost to produce a vesc is still so low that you can replace one and then you are have still profit. I repaired on on my own cost.
I am using this board for over 800km without any problem. Have done much more things that ask much more power.
This is no proof for you? The bms measure everything each milisecond.
I had a talk with @esk8manbabes. Can inference kill components? I had many times a disconnect in that corner. But the last time I had killed bass in the same corner. See video of a disconnect
Not possible is the Attitude of some one that can’t be arsed, go back to walking every or been carried.
Wouldn’t a mini cvt be a similar size to a gear drive?
Cvt is a high efficiency loss gearbox that hates foreign debris, large in profile, excessive weight and in a mini form would be a slip slip break on any high Watt application. They work great on side by sides and snow machines with the weak point being the belt.
With Subaru & Ford some tech is getting better but still weak link.
For a gas engine it is a slam dunk. The more you can focus keeping a gas motor in its optimal rpm torque curve the better.
How about going outside the box and having the wheel hub compress the wheel squishing it out giving a larger diameter for higher speed. Or a Motor and controller that can use windings differently depending on rpm
Variable Motor timing might be somthing to Play with also and could be esc manipulated. Will be interesting to see what ideas get used if 2kw or less Street regulations are implemented and enforced.
One of the best traits of electric is its instant and long torque curve
while many of you like to go fast i feel like there is a section of the mtb scene can’t grow until more power is available on tap. the folks going uphill on gravel and mud on big wheels. the ski lift crowd. the folks riding 80mm motors.
I did debate your matter with Benjamin and we looked at the damage.
The only possible explanation is a cutout from the BMS switch, which is probably microprocessor controlled. A short cut-out is enough! Usually the VESC shuts down when it sees a spike in voltage but if there is no battery attached, the voltage rises so fast inside the VESC, it blows up before the VESC can react.A big capacitor bank would give the VESC a bit more time to react.
The recordings on your phone are probably not showing the event, since the connection from the BMS to the phone is too slow to track a single event and the BMS hasn’t seen an over voltage event anyway, it probably just shut down the switch for a second.
We have seen the same on mosfet switches. In one case the physical switch had a wiggle waggle, Mosfet switch did cot out and VESC blew up.
We tried to solve that matter by implementing the switch on the VESC itself, which is more of a hibernation mode than a real switch that can fail. The idea is to strip out parts that are in between the battery and the VESC. A simple charge only BMS would do the job in this case. Your case is more tragic, since you had the MKIII model and still used the switch in the BMS.
Please understand that we can’t warrant damages that are not caused by our hardware.
We have always been very generous with replacements, we even sent out new decks to guys who slammed their boards full speed into a obstacle. I had a customer who blew up 3 VESC 75/300 before he found out that the motor had a short to GND. One of them was a complete loss, two could be fixed by Benjamin. However, we can’t replace all the stuff that people blow up, If we are not sure, we take it on us, but in your case it’s very obvious that something in the system shot two VESCs into ESC heaven.
I can guarantee you that any other ESC would have also blown up the very same way.
Inference can cause issues. It can make devices non operative and there can be a chain reaction. I haven’t heard of such a thing yet, but I can imagine it happens. Anything that is microprocessor controlled is dependent on it functioning. The processors inside the VESC are shielded by the housing though.
We just sent a bunch of VESCs to seaborder for repair. Returns that gathered up over the last 12 months.
There are 3 x MKIII in the box. If he can fix one, we can help you out with such a unit.
See that’s a cool service! It would be awesome if that is possible! Thanks!
Higher voltage and higher gear reduction ratios could help with that.
Higher gear reduction would help as well as bigger motors. Voltage does not matter, you can achieve the same on 10,12,14,16, 20S without any relevant efficiency impact. The higher voltage might be slightly more efficient, but that is more theoretical than a real life improvement. Gearing has the biggest impact on efficiency and torque output. Simply use a faster motor and more gearing if you can. There is enough ERPM headroom in the modern VESC designs these days. You can drive 300KV motors without any issues.
It has nothing to do with a skateboard, but the 13-14s goes well with a 48V rated DCAC inverter.
4.2V ×14s = 58.8V
2.8V × 14s = 39.2V
The rated 48V DCAC inverter has a maximum of 60V and a cutoff of 40V.
ESK8 can be used as off-grid power supply.
Well, in that case 10s goes well with a 36v one. 30-45v
