10S custom skate ESC: testers wanted!

Lightweight / Folding / Portable EVs - seats optional
vedder   100 W

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Re: 10S custom skate ESC: testers wanted!

Post by vedder » Nov 13 2015 5:56am

chuttney1 wrote:
F3-John wrote: Outrunner with 1200kv
Inrunner 4 Poles with 2500kv
I must say 1200 Kv for Outrunner and 2500 Kv for an inrunner is very high, not useful for eboards. I am assuming you have other applications with the VESC you want to test...
I think these motors should work, but you have to adjust the detection parameters. The default parameters work for most 100 to 500kv 50 to 60mm eboard outrunners, but for these motors you have to change the current a bit.

Does the inrunner happen to be a coreless one (you will notice this if it has very low cogging torque when turning it by hand)? They don't work too well with the integration mode since they have very low inductance. The coreless motors I have happen to be very inefficient as well, so I think most hobby coreless motors have a quite bad construction.
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Maxi   1 µW

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Re: 10S custom skate ESC: testers wanted!

Post by Maxi » Nov 13 2015 6:45am

Hi,

I'm new in this group and like to make some tests with CAN connected VESCs.
chaka wrote:Version 4.10 is confirmed, finished testing the first batch last night. I am placing an order for 50 PCB's if anyone is interested.
Are still some available? I'm interested in four. I've allready the Mouser parts. How much it would cost? How to organize PCB/money transfer?

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chaka   1 kW

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Re: 10S custom skate ESC: testers wanted!

Post by chaka » Nov 13 2015 10:04am

Maxi wrote:Are still some available? I'm interested in four. I've allready the Mouser parts. How much it would cost? How to organize PCB/money transfer?
I uploaded version 4.10 to OSHPark https://oshpark.com/shared_projects/NNzfrwPG This upload has been fully tested and confirmed.

F3-John   10 µW

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Re: 10S custom skate ESC: testers wanted!

Post by F3-John » Nov 13 2015 2:11pm

The ESC is for a RC Boat with 8s at 2500kv with 120A. (I know the VESC isn't made for 120A....its just for testing).

The Inrunner has a high cogging tourque ;)


I resoldered the DRV and the MC and change the Detection parameters to 15A an 1000RPM. The detection was good an i overwrite the values for BEMF Coupling (1400) and integrator Limit (40). I choose the PPM App to control the motor.

But: sometimes the motor does nur run.....it is just vibrating with high current. I think the motor doesnt get in rotation. I try to change some values without success. I have this Problem with both Motors. I have the feeling in Delay mode this problem is getting bigger. When the Motor get in rotation ist runs very fine ;)

Image

in the Picture the motor rotates from 14sek to 24sek....the rest is just vibration.

I hope you can help me.....

gearsarespinning   1 mW

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Re: 10S custom skate ESC: testers wanted!

Post by gearsarespinning » Nov 14 2015 3:35am

Decided to change out my 6s, hobbywing esc, LifePO4 system with the VESC and SpaceCell. Just received the new VESC 10.4 and Plugged in the battery, nunchuck and computer, started detection (per instructions) and it spun up. I filled in the info per the instructions then changed some of the motor settings optomized for the spacecell. I made the nunchuck settings and the little motor wasn't spinning. I know the nunchuk worked as I saw the display bar go up and down when I throttled. I made sure the current was checked, rebooted and connected again. The display bar does a little dance between 50 and 51 but still goes up and down with the joystick. I went back to the motor settings again and tried detection - the motor just makes a high pitched sound and jitters a bit. I am now at this and I am sure it is something simple. I looked and several forums, google searches and messed around with the settings but nothing helped. I even went back to the original settings but nothing worked. I have an NTM 5060 motor, plan is to upgrade this as well but need to get the new system working first. Here are some pics of the VESC in case it helps.

Has anyone else had this issue.I couldnt find anyone else in the forum so I just figurd it was something simple I am doing wrong.

Would appreciate anyone's help to get this badboy working - Thanks
Attachments
IMG_1601.JPG
vesc 4.10
IMG_1602.JPG
vesc 4.10

jamesonotc   10 W

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Re: 10S custom skate ESC: testers wanted!

Post by jamesonotc » Nov 14 2015 11:01am

F3-John wrote:Hello Guys,

last week i got one VESC PCB (V4.7) and ordered the parts from Mouser (BOM 4.7). Now i have assembled the VESC and flashed the Firmware (1.10). I can connect the VESC with the PC an can run my motor.

But the detection of the Motor paramters do not work. I get the Message (Bad detection). And when i run the motor without detection with standart parameters it runs very hard. I tried this with 2 different motors.
Outrunner with 1200kv
Inrunner 4 Poles with 2500kv

There are no Faults or flasching red Led

I hope you guys can help me.
make sure to clean up the pins on the DRV chip very well... my guess is you have a solder bridge between two of the pins somewhere it shouldnt.

My recommendation is to use solder wick to pull up any excess solder on the DRV chip and if that does not fix it clean up the STM32 pins..

this is an all to common occurrence.

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chaka   1 kW

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Re: 10S custom skate ESC: testers wanted!

Post by chaka » Nov 14 2015 11:40am

Looks like there might be a small bridge on the DRV chip by C22.

F3-John   10 µW

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Re: 10S custom skate ESC: testers wanted!

Post by F3-John » Nov 15 2015 7:15am

jamesonotc wrote:
F3-John wrote:Hello Guys,

last week i got one VESC PCB (V4.7) and ordered the parts from Mouser (BOM 4.7). Now i have assembled the VESC and flashed the Firmware (1.10). I can connect the VESC with the PC an can run my motor.

But the detection of the Motor paramters do not work. I get the Message (Bad detection). And when i run the motor without detection with standart parameters it runs very hard. I tried this with 2 different motors.
Outrunner with 1200kv
Inrunner 4 Poles with 2500kv

There are no Faults or flasching red Led

I hope you guys can help me.
make sure to clean up the pins on the DRV chip very well... my guess is you have a solder bridge between two of the pins somewhere it shouldnt.

My recommendation is to use solder wick to pull up any excess solder on the DRV chip and if that does not fix it clean up the STM32 pins..

this is an all to common occurrence.
Yes, i resoldered the STM and the DRV. But now i have another Problem. See 4 Posts above......

vedder   100 W

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Re: 10S custom skate ESC: testers wanted!

Post by vedder » Nov 15 2015 8:46am

I'm still working hard on FOC and made more progress this weekend, but I haven't pushed the code to github just yet. The more I work on it, the more things to fix I find. I hope I will have the first implementation ready to push soon with firmware 2.0.
F3-John wrote:The ESC is for a RC Boat with 8s at 2500kv with 120A. (I know the VESC isn't made for 120A....its just for testing).

The Inrunner has a high cogging tourque ;)


I resoldered the DRV and the MC and change the Detection parameters to 15A an 1000RPM. The detection was good an i overwrite the values for BEMF Coupling (1400) and integrator Limit (40). I choose the PPM App to control the motor.

But: sometimes the motor does nur run.....it is just vibrating with high current. I think the motor doesnt get in rotation. I try to change some values without success. I have this Problem with both Motors. I have the feeling in Delay mode this problem is getting bigger. When the Motor get in rotation ist runs very fine ;)

I hope you can help me.....
You can increase the min rpm in the sensorless tab, that should help. 1400 coupling sound a bit high, try 800 or so.

A 2500 kv4 pole motor at 8s will reach 160000 electrical RPM, so that will cause problems and your vesc will die for sure. You should not run that motor with more that 5s at most with the vesc.
gearsarespinning wrote:Decided to change out my 6s, hobbywing esc, LifePO4 system with the VESC and SpaceCell. Just received the new VESC 10.4 and Plugged in the battery, nunchuck and computer, started detection (per instructions) and it spun up. I filled in the info per the instructions then changed some of the motor settings optomized for the spacecell. I made the nunchuck settings and the little motor wasn't spinning. I know the nunchuk worked as I saw the display bar go up and down when I throttled. I made sure the current was checked, rebooted and connected again. The display bar does a little dance between 50 and 51 but still goes up and down with the joystick. I went back to the motor settings again and tried detection - the motor just makes a high pitched sound and jitters a bit. I am now at this and I am sure it is something simple. I looked and several forums, google searches and messed around with the settings but nothing helped. I even went back to the original settings but nothing worked. I have an NTM 5060 motor, plan is to upgrade this as well but need to get the new system working first. Here are some pics of the VESC in case it helps.

Has anyone else had this issue.I couldnt find anyone else in the forum so I just figurd it was something simple I am doing wrong.

Would appreciate anyone's help to get this badboy working - Thanks
Is there any fault code? What did you set the current limits to?
Some of my projects: http://vedder.se
Support my open source ESC development with a small donation

F3-John   10 µW

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Re: 10S custom skate ESC: testers wanted!

Post by F3-John » Nov 15 2015 10:10am

vedder wrote:
F3-John wrote:The ESC is for a RC Boat with 8s at 2500kv with 120A. (I know the VESC isn't made for 120A....its just for testing).

The Inrunner has a high cogging tourque ;)


I resoldered the DRV and the MC and change the Detection parameters to 15A an 1000RPM. The detection was good an i overwrite the values for BEMF Coupling (1400) and integrator Limit (40). I choose the PPM App to control the motor.

But: sometimes the motor does nur run.....it is just vibrating with high current. I think the motor doesnt get in rotation. I try to change some values without success. I have this Problem with both Motors. I have the feeling in Delay mode this problem is getting bigger. When the Motor get in rotation ist runs very fine ;)

I hope you can help me.....
You can increase the min rpm in the sensorless tab, that should help. 1400 coupling sound a bit high, try 800 or so.

A 2500 kv4 pole motor at 8s will reach 160000 electrical RPM, so that will cause problems and your vesc will die for sure. You should not run that motor with more that 5s at most with the vesc.
hello Vedder

which problems do you mean? Firmware problems or Hardware problems?
What max eRPM would be possible in Firmware?
How do you calculate the eRPM?

Maxi   1 µW

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Re: 10S custom skate ESC: testers wanted!

Post by Maxi » Nov 15 2015 10:29am

hey chaka,

thanks for your hint and activity!!
chaka wrote:
Maxi wrote:Are still some available? I'm interested in four. I've allready the Mouser parts. How much it would cost? How to organize PCB/money transfer?
I uploaded version 4.10 to OSHPark https://oshpark.com/shared_projects/NNzfrwPG This upload has been fully tested and confirmed.


I allready ordered three PCB for 19$. I'm little bit confused about the low cost as VESC is about 4 square inch and has a four layer design?!

According to the pricing of OSH park it should cost the double.

"There are currently three types of orders:
The standard 2 layer order
$5 per square inch, which includes three copies of your design. For example, a 2 square inch board would cost $10 and you’d get three copies of your board. You can order as many copies as you want, as long as they’re in multiples of three.

The standard 4 layer order
$10 per square inch, which includes three copies of your design. For example, a 2 square inch board would cost $20 and you’d get three copies of your board. You can order as many copies as you want, as long as they’re in multiples of three."

Will I get three four layer or two layer PCB?

Maxi

vedder   100 W

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Re: 10S custom skate ESC: testers wanted!

Post by vedder » Nov 15 2015 11:09am

F3-John wrote: hello Vedder

which problems do you mean? Firmware problems or Hardware problems?
What max eRPM would be possible in Firmware?
How do you calculate the eRPM?
Increase the Minimum ERPM from the default of 150 to something like 800.

You calculate the ERPM with kv * voltage * (motor poles / 2).

The problem is that the switching frequency (40 khz) is too low to get enough samples to track the motor at that speed, and the estimator will loose tracking. The commutation frequency at that rpm is 16 khz, which means that there are less than three samples for each commutation, which is too little to detect the zero crossing and integrate the back emf after that. Both the hardware and software make it difficult to increase the switching frequency since the drv8302 cannot drive the fets so fast and the software will take too much computational power. To run at higher speed a different power stage is needed and the software has to be optimized and simplified (no current and temperature limit calculations ever pwm cycle and bemf integration).
Some of my projects: http://vedder.se
Support my open source ESC development with a small donation

F3-John   10 µW

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Re: 10S custom skate ESC: testers wanted!

Post by F3-John » Nov 15 2015 12:30pm

vedder wrote:
F3-John wrote: hello Vedder

which problems do you mean? Firmware problems or Hardware problems?
What max eRPM would be possible in Firmware?
How do you calculate the eRPM?
Increase the Minimum ERPM from the default of 150 to something like 800.

You calculate the ERPM with kv * voltage * (motor poles / 2).

The problem is that the switching frequency (40 khz) is too low to get enough samples to track the motor at that speed, and the estimator will loose tracking. The commutation frequency at that rpm is 16 khz, which means that there are less than three samples for each commutation, which is too little to detect the zero crossing and integrate the back emf after that. Both the hardware and software make it difficult to increase the switching frequency since the drv8302 cannot drive the fets so fast and the software will take too much computational power. To run at higher speed a different power stage is needed and the software has to be optimized and simplified (no current and temperature limit calculations ever pwm cycle and bemf integration).

hello Vedder,
I understand the Problem.....not nice to hear but it is acceptable.
Maybe i can go on a 6s Setup with 180A do you think the detection will work up to 120.000 eRPM? I cant go down to 5s....
I even know that 180A is much too high for your VESC but iam working on a schematic with another Power Stage.

I have another Question: is it possible to set the Duty Cycle to 1.00 to reduce the switching losses?
We run our boats just 10sek......by 180A at 6s....after that we have 1 minute to cool down the system. But the switching losses at 180A are very high and iam note sure which Duty cycle other esc's (swordfisch, flier, YEP....) use.

gearsarespinning   1 mW

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Re: 10S custom skate ESC: testers wanted!

Post by gearsarespinning » Nov 16 2015 3:01am

gearsarespinning wrote:
Decided to change out my 6s, hobbywing esc, LifePO4 system with the VESC and SpaceCell. Just received the new VESC 10.4 and Plugged in the battery, nunchuck and computer, started detection (per instructions) and it spun up. I filled in the info per the instructions then changed some of the motor settings optomized for the spacecell. I made the nunchuck settings and the little motor wasn't spinning. I know the nunchuk worked as I saw the display bar go up and down when I throttled. I made sure the current was checked, rebooted and connected again. The display bar does a little dance between 50 and 51 but still goes up and down with the joystick. I went back to the motor settings again and tried detection - the motor just makes a high pitched sound and jitters a bit. I am now at this and I am sure it is something simple. I looked and several forums, google searches and messed around with the settings but nothing helped. I even went back to the original settings but nothing worked. I have an NTM 5060 motor, plan is to upgrade this as well but need to get the new system working first. Here are some pics of the VESC in case it helps.

Has anyone else had this issue.I couldnt find anyone else in the forum so I just figurd it was something simple I am doing wrong.

Would appreciate anyone's help to get this badboy working - Thanks


Is there any fault code? What did you set the current limits to?

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Top
Not sure where to find the fault code. I went into realtime data and no codes

Current limits are
60
-60
30
-20
130

Based on what on loop suggested for the space cell.

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chaka   1 kW

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Re: 10S custom skate ESC: testers wanted!

Post by chaka » Nov 16 2015 9:42am

Within the BLDC tool you will find a tab marked "terminal". Type the command "faults" and it will show any faults recorded since start up.
Last edited by chaka on Nov 17 2015 9:42pm, edited 1 time in total.

gearsarespinning   1 mW

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Re: 10S custom skate ESC: testers wanted!

Post by gearsarespinning » Nov 16 2015 12:19pm

Thanks chaka, no faults since start up.

Just to make sure it wasn't the motor I hooked it up to my 6s system and worked well.

gearsarespinning   1 mW

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Re: 10S custom skate ESC: testers wanted!

Post by gearsarespinning » Nov 16 2015 1:22pm

gearsarespinning wrote:
Decided to change out my 6s, hobbywing esc, LifePO4 system with the VESC and SpaceCell. Just received the new VESC 10.4 and Plugged in the battery, nunchuck and computer, started detection (per instructions) and it spun up. I filled in the info per the instructions then changed some of the motor settings optomized for the spacecell. I made the nunchuck settings and the little motor wasn't spinning. I know the nunchuk worked as I saw the display bar go up and down when I throttled. I made sure the current was checked, rebooted and connected again. The display bar does a little dance between 50 and 51 but still goes up and down with the joystick. I went back to the motor settings again and tried detection - the motor just makes a high pitched sound and jitters a bit. I am now at this and I am sure it is something simple. I looked and several forums, google searches and messed around with the settings but nothing helped. I even went back to the original settings but nothing worked. I have an NTM 5060 motor, plan is to upgrade this as well but need to get the new system working first. Here are some pics of the VESC in case it helps.

Has anyone else had this issue.I couldnt find anyone else in the forum so I just figurd it was something simple I am doing wrong.

Would appreciate anyone's help to get this badboy working - Thanks


Is there any fault code? What did you set the current limits to?

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Joined: Sat Nov 05, 2011 7:37 pm
Top


Not sure where to find the fault code. I went into realtime data and no codes

Current limits are
60
-60
30
-20
130

Update - I reflashed the firmware to Default, read configurations, started detection and it spun up. WOOOHOOO!!

Thanks everyone for taking the time to help me out.

Ill let you know how the rest of the setup goes.

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Re: 10S custom skate ESC: testers wanted!

Post by exco » Nov 17 2015 6:17pm

tho whom it may concern ;-)

howto connect an el cheapo bluetooth-serial module (e.g. HC-06)
Connect a usb-serial to the bluetooth module (5v, gnd, rx<->tx, tx<->rx)

AT commands to setup baud rate, name, pin.

When there's no active bluetooth connection the HC-06 defaults to "AT" mode and you can set it up to your needs.

You can test the bt-serial connection e.g. if you have a built-in bt module in your pc.

Check if there's /dev/rfcomm after establishing a bt connection to the module.
If not you need to setup the bluetooth-serial connection e.g. in ubuntu like this:

Code: Select all

hcitool scan
#comment ^^ get the mac (e.g. 00:12:06:DE:E1:B3)
sudo rfcomm connect /dev/rfcomm0 <mac>
#comment try the connection:
#comment console 1: bluetooth serial (built in bluetooth module)
sudo minicom –device /dev/rfcomm0 –baudrate 9600
#comment console 2: usb serial connected to hc-06 module
sudo minicom -device /dev/ttyUSB0 -baudrate 9600
#comment if you add your user to dialout group you don't need root permissions ;-)

#comment ^^ type some stuff  (should display in both minicom sessions)
So after setting up the module connect the bluetooth module to the VESC P3 connector. P3: [5V, not4us , gnd, not4us, tx, rx]

I setup the HC-06 with 9600 baud - so you need to set the UART baud rate for the VESC UART to 9600 and
additionally you need to change the baud rate for bldc-tool in mainwindow.cpp in bldc-tool line 1799 to

Code: Select all

     mSerialPort->setBaudRate(QSerialPort::Baud9600);
and recompile with "make -j4" (or however many cores you have to speed up things).


Afterwards you can connect to your VESC with bldc-tool through e.g. /dev/rfcomm0

bldc-tool connected through bluetooth
Image

vedder controller with hc-06 bluetooth module
Image

^^ feel free to use this as a starting point putting it in the VESC FAQ
or a proper wiki (hint hint @vedder)

Now it would really be awesome to be able to connect to the VESC with jacobbloy's android app (thread here).

of course the hc-06 is a shitty module - but that's what I had at hand.
Last edited by exco on Nov 18 2015 4:05pm, edited 1 time in total.
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tomtnt   10 W

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Re: 10S custom skate ESC: testers wanted!

Post by tomtnt » Nov 18 2015 12:32am

I noticed the "mellow drive" board has an "endless ride" where you kick once and the cruise control automatically turns on to keep that low speed cruising. Is it currently possible to do something like this on the VESC

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Re: 10S custom skate ESC: testers wanted!

Post by Vulthor » Nov 18 2015 6:15pm

tomtnt wrote:I noticed the "mellow drive" board has an "endless ride" where you kick once and the cruise control automatically turns on to keep that low speed cruising. Is it currently possible to do something like this on the VESC
This Is a really interesting function I would like to have!

Didn't see at the moment any video on this "endless ride"
"I pushed a button"

rodgah   10 kW

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Re: 10S custom skate ESC: testers wanted!

Post by rodgah » Nov 18 2015 6:25pm

If you use the Wii remote that Ben and jacobbloy have been working on, you can press and hold the cruise button after a few kicks and it will maintain that speed.
Common Sense isn't so common........
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Specialized BigHit
Electrapunk
Stinky

Vulthor   100 W

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Re: 10S custom skate ESC: testers wanted!

Post by Vulthor » Nov 18 2015 6:38pm

rodgah wrote:If you use the Wii remote that Ben and jacobbloy have been working on, you can press and hold the cruise button after a few kicks and it will maintain that speed.
Good to know, thanks for sharing.
"I pushed a button"

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Re: 10S custom skate ESC: testers wanted!

Post by okp » Nov 19 2015 7:41am

yes, this is pretty impressive ! I use it all the time. Good thing too is that you can reverse the motor way; you can move from dual rear, to dual front just by pressing the Z button

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Re: 10S custom skate ESC: testers wanted!

Post by NyOliver » Nov 19 2015 12:33pm

I'm looking for a confirmation that 260kv and 12s work fine. This will be my first build and since I'm going to be in traffic with Manhattan streets I will be happy with a lower top speed. looking for efficiency and smoothness of operation...

Here's the calculator of what I'm about to buy:


Efficiency (%) 70
Battery volts
44.4
Motor RPM
11544
Weighted Motor RPM
8081


Gearing ratio
3.54 : 1
Top Speed Calculations
Top Speed
26.75 mph / 43.05 kph
Weighted Top Speed
18.72 mph / 30.13 kph on 70mm wheels.

The attached image is just a screenshot of the calculator.
Attachments
image.jpeg
6354 sk3 motor
image.jpeg (211.01 KiB) Viewed 853 times

elkick   100 W

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Re: 10S custom skate ESC: testers wanted!

Post by elkick » Nov 19 2015 3:35pm

Vanarian wrote:As some of you know, I lost my 2 VESCs in the hand of Marcin who did never sent them back to me after repair/replacement. I live in France, EU. Do any of you know of a VESC builder in the EU?
We started production of VESC's in Germany since there is no source in Europe at the moment. Although we will ship worldwide and since it's a local factory producing and assembling the VESC it will be in stock permanently. Pls check here: https://endless-sphere.com/forums/viewt ... 31&t=74335
http://www.esk8.de/vesc VESC V4.12 - made in Germany
http://www.esk8.de/shop General eSkateboard parts

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