Search found 13729 matches

by John in CR
Dec 07 2019 10:13pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: HELP a noob pls- Replacing my burnt controller 60V
Replies: 7
Views: 167

Re: HELP a noob pls- Replacing my burnt controller 60V

The resistance to turning the wheel that goes away when the phase wires are disconnected from the controller is a sure sign of shorted mosfets in the controller. It quite commonly occurs during a takeoff when the controller is already hot from use, because takeoff is when phase currents are the high...
by John in CR
Dec 07 2019 9:51pm
Forum: Battery Technology
Topic: Parallel "Groups" or Parallel Strings or Neither ?
Replies: 51
Views: 1036

Re: Parallel "Groups" or Parallel Strings or Neither ?

Personally I would never use pure nickel strip for series connections, because nickel has 4X the resistance of copper. Instead I'd used nickel plated copper strips to retain the easy to tab weld properties of nickel as well as its resistance to corrosion.Pure nickel strip is fine for the parallel co...
by John in CR
Dec 07 2019 5:58am
Forum: E-Scooter and Motorcycle General Discussion
Topic: New Project " help Please" Honda st1300 Conversion
Replies: 27
Views: 1118

Re: New Project " help Please" Honda st1300 Conversion

I'm trying to help you not make the same mistakes plenty of engineers have made when approaching an EV build. Everyone who's mechanically inclined thinks in the beginning that they'd somehow be better off with a clutch and multiple gears. I thought the same way too. Even Tesla wasted millions in the...
by John in CR
Dec 07 2019 3:48am
Forum: E-Scooter and Motorcycle General Discussion
Topic: HELP a noob pls- Replacing my burnt controller 60V
Replies: 7
Views: 167

Re: HELP a noob pls- Replacing my burnt controller 60V

How do you know the controller is fried and not the motor or both, since a motor failure can fry a controller? Other culprits stopping your ride could be the throttle, the brake cutoff, or even a bad connection anywhere in the electrical pathways. If you don't already have a basic multimeter and ebi...
by John in CR
Dec 06 2019 6:34pm
Forum: Battery Technology
Topic: Parallel "Groups" or Parallel Strings or Neither ?
Replies: 51
Views: 1036

Re: Parallel "Groups" or Parallel Strings or Neither ?

The problem with putting series strings together in parallel with only small gauge parallel connections at the cell level is, what happens when one cell in the pack is weak or is dead. ie high current will try to pass through small wires. Other than maybe some of those handmade Chinese packs that so...
by John in CR
Dec 06 2019 5:07am
Forum: E-Bike Technical
Topic: Nucular Electronics owner's thread (setup infos, FW updates, links etc.)
Replies: 211
Views: 15830

Re: Nucular Electronics owner's thread (setup infos, FW updates, links etc.)

Yes, I understand that. That is why I was so sure that I tried auto, then shanged to remote when it did´nt work. But when I later shanged to auto again for whatever reason, I noticed that the switch worked. Ah, I'm not the only one with some "ghosts in the machine" activity that magically disappear...
by John in CR
Dec 05 2019 10:27pm
Forum: Battery Technology
Topic: Parallel "Groups" or Parallel Strings or Neither ?
Replies: 51
Views: 1036

Re: Parallel "Groups" or Parallel Strings or Neither ?

Strings to me means multiple cells or batteries, so it applies best to series. Parallel "groups" can essentially be treated as if together they are a single cell with the summed amp-hour capacity. While you can group series strings together in parallel, if they aren't paralleled together at the cell...
by John in CR
Dec 05 2019 6:41pm
Forum: E-Bike Technical
Topic: help motor run reverse
Replies: 17
Views: 555

Re: help motor run reverse

First do JohnCR trick of swapping any two wires as I read he can do it in 6 tries ? It took me 36 and a piece of paper and and only one worked ? After the 22nd I kept going just to know. A bmc 600 geared a very fickle motor. Don't worry you will find it. Good luck. I've heard the story of 1 in 36 f...
by John in CR
Dec 05 2019 12:42pm
Forum: E-Bike Technical
Topic: help motor run reverse
Replies: 17
Views: 555

Re: help motor run reverse

No, but the flow chart thing is a bit of a time waster too. Wiring configs are a simple problem with a simple solution that I explained in a few sentences. I could do it blindfolded, so anyone can do it.
by John in CR
Dec 05 2019 6:27am
Forum: E-Bike Technical
Topic: Nucular Electronics owner's thread (setup infos, FW updates, links etc.)
Replies: 211
Views: 15830

Re: Nucular Electronics owner's thread (setup infos, FW updates, links etc.)

Dual Nucs is working great on my 6 phase motors. I can't wait till the master slave option is up and running, so my display gives system stats. One difference I found that is different from the Control support section recommendation is when using a switch for on/off, setting one controller to source...
by John in CR
Dec 05 2019 6:14am
Forum: E-Bike Technical
Topic: help motor run reverse
Replies: 17
Views: 555

Re: help motor run reverse

If no self leaning is taking place with the controller, then you are getting mixed results...a true reverse and a false positive reverse denoted by a rougher start, a lack of torque, higher no load current, and typically higher max rpm due to the advanced timing of the incorrect wiring config. If it...
by John in CR
Dec 05 2019 1:01am
Forum: E-Scooter and Motorcycle General Discussion
Topic: New Project " help Please" Honda st1300 Conversion
Replies: 27
Views: 1118

Re: New Project " help Please" Honda st1300 Conversion

Time to back up a bit. How much does that thing weigh without motor, transmission (not needed unless you need a low gear for long mountain climbs with a big load), gas tank, etc? It looks heavy to me, and if you're going to all the trouble of building a beautiful EV you want it to be fun. It's not t...
by John in CR
Dec 03 2019 6:51pm
Forum: Battery Technology
Topic: Best Method for Battery Build??? 16s4p Telsa 2170 Cells
Replies: 20
Views: 951

Re: Best Method for Battery Build??? 16s4p Telsa 2170 Cells

The volt battery performed nicely, it was a modded meanwell that short circuited while charging that ultimately fried the battery. I don't think you can have both factory wiring and keeping it close to bike width. You could possibly maybe get a large section cut out with the original busses but it ...
by John in CR
Dec 03 2019 8:45am
Forum: Battery Technology
Topic: Best Method for Battery Build??? 16s4p Telsa 2170 Cells
Replies: 20
Views: 951

Re: Best Method for Battery Build??? 16s4p Telsa 2170 Cells

They are down to single cells clean and ready to build into custom sized packs. Yes, but that's so much work, and I by far prefer to use factory connections when possible. My Volt modules perform beautifully, and you killed yours, though possibly due to aggressive charge/discharge levels...or not a...
by John in CR
Dec 03 2019 2:08am
Forum: Battery Technology
Topic: High AMP battery build
Replies: 6
Views: 452

Re: High AMP battery build

...and all that sag Amberwolf is showing you is coming just from the internal resistance of the cell, so it's all turning to heat. Do the math and heat problems are guaranteed at 500A even with perfect connections to and between the cells. If ridden fairly easily with short bursts of high current th...
by John in CR
Dec 03 2019 1:42am
Forum: Battery Technology
Topic: Best Method for Battery Build??? 16s4p Telsa 2170 Cells
Replies: 20
Views: 951

Re: Best Method for Battery Build??? 16s4p Telsa 2170 Cells

Just recently got the Tesla Model 3 battery in and managed to keep a segment together while dismantling. I plan on making it 16s4p and was thinking of wiring it with fuse wire in the Tesla fashion. Need some opinions please. 20191120_144034(1)~2.jpg Also have a few hundred cells available to buy fo...
by John in CR
Dec 01 2019 8:27pm
Forum: Battery Technology
Topic: Criticise my modular pack design idea. 28s * 1s20p
Replies: 12
Views: 603

Re: Criticise my modular pack design idea. 28s * 1s20p

Cylindrical cells arranged in straight rows and columns like that wastes a ton of space, and space is the biggest premium on our ebikes. Instead of those holders, I'd suggest gluing the blocks of parallel cells in a staggered alignment like Tesla does. Don't use hot glue like some do, as it simply ...
by John in CR
Dec 01 2019 4:43am
Forum: Battery Technology
Topic: DIY High Cell Count Balance Charger for Cheap
Replies: 27
Views: 1417

Re: DIY High Cell Count Balance Charger for Cheap

I find it hard to believe that your cells are within 1.5% after repeated use and charging cycles. You must be accustomed to the crappy batteries so commonly used. Get yourself some automotive grade batteries and then you'll understand. BTW my packs are many times closer to perfect balance than 1.5%...
by John in CR
Dec 01 2019 4:13am
Forum: Battery Technology
Topic: Criticise my modular pack design idea. 28s * 1s20p
Replies: 12
Views: 603

Re: Criticise my modular pack design idea. 28s * 1s20p

Cylindrical cells arranged in straight rows and columns like that wastes a ton of space, and space is the biggest premium on our ebikes. Instead of those holders, I'd suggest gluing the blocks of parallel cells in a staggered alignment like Tesla does. Don't use hot glue like some do, as it simply d...
by John in CR
Nov 28 2019 5:35am
Forum: Battery Technology
Topic: Building my own battery module PART 1
Replies: 21
Views: 1264

Re: Building my own battery module PART 1

The most important thing is not a BMS. The most important thing since your intended use is on a boat is keeping the battery dry, especially if used in salt water. Automotive grade batteries maintain balance so well with conservative use that with conservative charge and discharge levels occasional c...
by John in CR
Nov 28 2019 4:22am
Forum: Battery Technology
Topic: DIY High Cell Count Balance Charger for Cheap
Replies: 27
Views: 1417

Re: DIY High Cell Count Balance Charger for Cheap

How do you reconcile the fact that using 1 cheap 20s BMS board is scary with the fact that 20 cheap 1s charger boards is over 20 times scarier, especially since in the best case they are killing your pack much faster and result in greater pack imbalance after one day than I have had in 11 years runn...
by John in CR
Nov 28 2019 4:06am
Forum: Battery Technology
Topic: Reduce noise of fanned charger
Replies: 7
Views: 325

Re: Reduce noise of fanned charger

Something I've done with chargers that will get mistreated and exposed is to build a wooden box and secure the charger in it. Then I mount 2 larger diameter more quiet fans (for redundancy in case one fails), one at each end of the box (one blowing in and one blowing out). Be sure to orient the char...
by John in CR
Nov 23 2019 9:02pm
Forum: E-Bike General Discussion
Topic: How fast can my 250W chinese motor go?
Replies: 23
Views: 926

Re: How fast can my 250W chinese motor go?

The 25kph max speed listed seems reasonable. 20km on the 8ah battery doesn't seem reasonable though unless conditions are perfect...flat and smooth with dedicated cycling infrastructure, which is the only way I rid a little folder like that. That is perfect conditions and lots of pedal assist for th...
by John in CR
Nov 23 2019 8:27pm
Forum: Motor Technology
Topic: aluminum windings
Replies: 3
Views: 360

Re: aluminum windings

Most likely some super crappy motors to begin with with quite poor copper fill.

Where the hell are our cheap room temp superconductors? In the meantime I'll take some motors with cast copper windings for maximum fill.
by John in CR
Nov 23 2019 8:05pm
Forum: Motor Technology
Topic: Sur-Ron 16kw outrunner
Replies: 7
Views: 758

Re: Sur-Ron 16kw outrunner

Sounds like a pretty good motor. What's the phase-to-phase resistance? To me that's the most important spec when it comes to real world power handling. Personally I like much lower rpm for a quieter ride and accept the added motor weight, but for grins what's the no load current at the high rpm?