Search found 11742 matches

by fechter
Feb 21, 2018 9:13 am
Forum: E-Bike Technical
Topic: Speed control with a potentiometer
Replies: 19
Views: 310

Re: Speed control with a potentiometer

Something is wrong there. It should be zero. Either something is shorted inside the controller or the wires are mixed up. At this point, I would want to take a look inside the controller and see where that green wire is attached. If you remove the end panel, you might be able to see it without takin...
by fechter
Feb 20, 2018 10:32 pm
Forum: E-Bike Technical
Topic: Any good and simple "cop button" solutions?
Replies: 39
Views: 1176

Re: Any good and simple "cop button" solutions?

Something like that might work on a Bafang BBSxx as well. The display would power up and defaults to setting 1. When you hit the button to change levels, it would go up on the display, but not on the motor. I might have to try this to see if it works. Motor might not run at all if it gets nothing fr...
by fechter
Feb 20, 2018 11:46 am
Forum: E-Bike Technical
Topic: Speed control with a potentiometer
Replies: 19
Views: 310

Re: Speed control with a potentiometer

Hmm... seems like maybe you have a defective controller. You might try opening the case and do an inspection of the wires inside. sometimes you can see something obvious. One more test; if you leave the green throttle wire disconnected, try measuring the voltage on it against battery negative. Norma...
by fechter
Feb 19, 2018 4:50 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 487
Views: 26616

Re: Sur-Ron - New Mid drive Bike from China

Seems like it wouldn't be too hard to make a cover to enclose the primary belt to keep dirt from getting on it.
by fechter
Feb 19, 2018 3:50 pm
Forum: Battery Technology
Topic: Motorcycle starter battery
Replies: 4
Views: 90

Re: Motorcycle starter battery

Are you using the 20Ahr A123 pouch cells? I don't think you can solder to those.
by fechter
Feb 19, 2018 3:33 pm
Forum: Motor Technology
Topic: Ferrofluid for hub cooling? BS or real?
Replies: 29
Views: 592

Re: Ferrofluid for hub cooling? BS or real?

howz bout iff either's good then do both must be better. FTW squared n'est-ce pas? what happens if you mix the two? concerned lemmings gotz 2no. touch o' da spring fever Probably a bad idea. The oil bases may not be compatible and the surfactant in the FF might not like it and cause all the iron pa...
by fechter
Feb 19, 2018 3:14 pm
Forum: E-Bike Photos & Video
Topic: BBSHD Takes on the Luiz Fire Road
Replies: 7
Views: 285

Re: BBSHD Takes on the Luiz Fire Road

richmpdx wrote:
Feb 16, 2018 11:51 am
Nice video, great ride location. Thanks for sharing. Interesting that the BBSHD handles the sustained climb with no problem. Obviously that is not your A2B, what's the ride?
Yes, the A2B wouldn't make it very far up that kind of grade. It's my fat bike:
Img_0654A.jpg
Img_0654A.jpg (131.83 KiB) Viewed 59 times
by fechter
Feb 19, 2018 2:59 pm
Forum: E-Bike Technical
Topic: Speed control with a potentiometer
Replies: 19
Views: 310

Re: Speed control with a potentiometer

If you disconnect the throttle green wire, does it stop running?
by fechter
Feb 19, 2018 1:56 pm
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 662
Views: 23042

Re: la Nina rears her ugly head

Freeze warning for here tonight. Down to 30 predicted. While balmy by Midwest standards, a lot of vegetation around here isn't built to survive freezing.
by fechter
Feb 19, 2018 1:52 pm
Forum: E-Bike Technical
Topic: Speed control with a potentiometer
Replies: 19
Views: 310

Re: Speed control with a potentiometer

Hard to see exactly in the picture. The potentiometer is wired reversed, so that clockwise will decrease speed. This won't matter except the way you turn it is reversed. Swap the two outer legs to make clockwise increase speed. I don't see the red wire going to the throttle. Do the measurement I sug...
by fechter
Feb 18, 2018 1:31 pm
Forum: E-Bike Technical
Topic: Speed control with a potentiometer
Replies: 19
Views: 310

Re: Speed control with a potentiometer

It sounds like you don't have a connection to the ground wire.
The black wire should be ground. Measure all three legs on the pot against battery negative.
by fechter
Feb 17, 2018 12:05 pm
Forum: E-Bike Technical
Topic: Speed control with a potentiometer
Replies: 19
Views: 310

Re: Speed control with a potentiometer

blue wire says speedometer, so don't use that one.
The green throttle wire goes to the middle leg on the pot.

The orange wire needs to be connected to the red wire to turn the controller on.
by fechter
Feb 16, 2018 1:13 pm
Forum: E-Bike Technical
Topic: Speed control with a potentiometer
Replies: 19
Views: 310

Re: Speed control with a potentiometer

You can use a regular potentiometer if you place fixed resistors in series with the 5v and ground wires. I would use a 5k pot, but the value is not critical. The fixed resistors for a 5k pot would be about 1.2k each. You want the signal to go from about 1v to 4v with a 5v source.
by fechter
Feb 15, 2018 9:27 am
Forum: E-Bike General Discussion
Topic: How To, 50A BBSHD Controller Mod
Replies: 142
Views: 10704

Re: How To, 50A BBSHD Controller Mod

If I am going to be replacing mosfets with better quality and higher voltage ratings, would this be a suitable candidate for this kind of modification? https://em3ev.com/shop/bafang-bbs02-48v-750w-controller/ It will be potted, so difficult to replace the FETs. If it has the 3077 FETs installed, th...
by fechter
Feb 14, 2018 8:09 pm
Forum: Alternative Energy
Topic: Need help with a transformer
Replies: 22
Views: 471

Re: Need help with a transformer

It will look like drawing 3. What you have is single phase, split phase.

A good description of it is here:
https://en.wikipedia.org/wiki/Split-pha ... tric_power
by fechter
Feb 14, 2018 9:16 am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 487
Views: 26616

Re: Sur-Ron - New Mid drive Bike from China

Interesting.

Here's a cut sheet for the BMS chip:

http://www.lapis-semi.com/en/data/leafl ... 238_en.pdf
Lapis BMS.JPG
Lapis BMS.JPG (125.9 KiB) Viewed 425 times
by fechter
Feb 14, 2018 12:22 am
Forum: E-Bike General Discussion
Topic: How To, 50A BBSHD Controller Mod
Replies: 142
Views: 10704

Re: How To, 50A BBSHD Controller Mod

I know the BBSHD I'm running has the shitty 75NF75 FETs, but it still does amazingly well. I don't run 30A for long periods either, but the motor heating is more of an issue than the controller heating for me. Someone measured one with a FLIR and the temps around the controller are higher than the r...
by fechter
Feb 13, 2018 8:07 pm
Forum: E-Bike General Discussion
Topic: How To, 50A BBSHD Controller Mod
Replies: 142
Views: 10704

Re: How To, 50A BBSHD Controller Mod

I don't know how to tell without taking it apart and looking at the markings on the FETs.

I have seen an enhanced housing with extra cooling fins that Luna makes. Not sure if they are sold separately or not.
by fechter
Feb 13, 2018 8:03 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike from China
Replies: 487
Views: 26616

Re: Sur-Ron - New Mid drive Bike from China

Wow, thanks for posting the teardown on the pack. Can you read the numbers on the BMS chips? It looks better than the typical cheap Chinese variety.
by fechter
Feb 13, 2018 3:03 pm
Forum: E-Bike General Discussion
Topic: More E-bikes found in NON-ebike media
Replies: 4802
Views: 199096

Re: More E-bikes found in NON-ebike media

NYC e-Bike Ban is Disaster for Immigrant Delivery Workers : https://www.voanews.com/a/new-york-city-e-bike-ban-immigrant-delivery-workers/4251812.html Some large ebike company with lots of money should help the delivery workers go on strike. Maybe selectively refuse deliveries to NYC lawmakers. Bik...
by fechter
Feb 13, 2018 2:58 pm
Forum: E-Bike Technical
Topic: Parallel throttle?
Replies: 6
Views: 194

Re: Parallel throttle?

Some throttles can sink as well as source. It depends on the hall sensor used.
by fechter
Feb 13, 2018 2:57 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 679
Views: 53320

Re: Active pre-charge/inrush control

I built a variation of the V3 inrush limiter design to use with my 12s 20Ah ebike pack. I'm using a normally open keyswitch to control it. I usually estimate about 20A per FET for minimal heat sinking. You should have no problems with heat as long as the board gets some air flow or against somethin...
by fechter
Feb 13, 2018 9:48 am
Forum: E-Bike Technical
Topic: Parallel throttle?
Replies: 6
Views: 194

Re: Parallel throttle?

I don't think you can just parallel the two as one could be fighting the other and possibly fry something. If each signal wire passed through a diode before being combined, then there would be no chance of backfeeding either one. The diode would result in a slightly lower signal voltage though, and ...
by fechter
Feb 13, 2018 9:42 am
Forum: E-Bike Technical
Topic: RCA 10.5 Connector for Battery Charger
Replies: 12
Views: 166

Re: RCA 10.5 Connector for Battery Charger

Just curious:
Was the fire caused by the bike?
by fechter
Feb 13, 2018 9:36 am
Forum: Battery Technology
Topic: Common pack design mistakes, how to avoid?
Replies: 236
Views: 18582

Re: Common pack design mistakes, how to avoid?

I've seen some packs that are completely potted, even over the vents (Grin LiGo, for example). I guess if the cell gets to the point where it wants to vent, you have bigger problems anyway. The foam stuff won't hold back a venting cell much anyway. If you could find some foam that doesn't expand muc...