Search found 14365 matches

by fechter
Apr 04 2020 8:05pm
Forum: Battery Technology
Topic: Lithium battery question
Replies: 81
Views: 4772

Re: Lithium battery question

The actual rating is dependent on temperature. The BMS is supposed to trip when it exceeds the “peak “ rating. How long you can go over the continuous rating depends on cooling.

It’s possible the one you fried was defective or rated higher than it was really capable of.
by fechter
Apr 04 2020 7:26pm
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 1692
Views: 118555

Re: la Nina rears her ugly head

Finally getting some rain here. Maybe it will help wash away all the coronaviruses.
by fechter
Apr 04 2020 7:25pm
Forum: E-Vehicles General Discussion
Topic: C Cab Hot Rod Power Advice
Replies: 354
Views: 16576

Re: C Cab Hot Rod Power Advice

Sweet. I used to have a Cub Cadet many years ago. Always wanted to convert it to electric but back then the parts sucked.
by fechter
Apr 03 2020 10:10am
Forum: Large EV General Discussion
Topic: Sevcon powerpak
Replies: 3
Views: 67

Re: Sevcon powerpak

Great solution! Was the chip soldered on or in a socket?
by fechter
Apr 02 2020 9:38am
Forum: Large EV General Discussion
Topic: Sevcon powerpak
Replies: 3
Views: 67

Re: Sevcon powerpak

There are like thousands of parameter settings in the software that need to more or less match what you had in the original controller. You also need a stupidly expensive programmer interface to make changes. Ideally you'd want to see if the OEM can give you the parameter settings file. If not, it w...
by fechter
Mar 31 2020 10:48am
Forum: E-Vehicles General Discussion
Topic: C Cab Hot Rod Power Advice
Replies: 354
Views: 16576

Re: C Cab Hot Rod Power Advice

I guess it would help to see what the linkage looks like on the front wheels. Is there some reason the Pitman arm can't be attached directly to the steering column? The arm would need to come out on the inside of the frame and the linkage would be a little diagonal to the attachment point on the fro...
by fechter
Mar 29 2020 10:07pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1017
Views: 86519

Re: APL's DIY axial-flux motor

Interesting but certainly seems complex. It seems like there would be a sacrifice of torque density, but I didn't read the whole paper.

I think your current design looks pretty good.
by fechter
Mar 28 2020 12:43pm
Forum: Items for Sale - New
Topic: Sur-Ron - Belt upgrade KIT
Replies: 107
Views: 15254

Re: Sur-Ron - Belt upgrade KIT

I found the spokes were resonating on mine. I placed zip ties on the spoke crossings and it was greatly reduced.
by fechter
Mar 28 2020 12:39pm
Forum: E-Bike Non-hub Motor Drives
Topic: 1.7kg 1000w mid drive
Replies: 51
Views: 6338

Re: 1.7kg 1000w mid drive

Timelord wrote:
Mar 25 2020 8:36pm
By the way, what is this topic doing in the Items for Sale forum? It should be in E-bike Non-hub Motor Drives.
Topic moved.
by fechter
Mar 26 2020 9:15am
Forum: E-Bike Technical
Topic: Controller Trips under load
Replies: 30
Views: 482

Re: Controller Trips under load

One test would be to get it running with the wheel up and slowly apply load while watching the voltage and current. See at what point does it trip. You can apply load with the brake if you disconnect the brake switch.
by fechter
Mar 26 2020 9:02am
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1017
Views: 86519

Re: APL's DIY axial-flux motor

I think the iron in your picture above will act like a one turn short in all cases. If you slot the iron radially to break the circuit it will be better, but you will still have some eddy currents in the iron. Something non-conductive is really what you want.
by fechter
Mar 25 2020 9:38am
Forum: E-Bike Non-hub Motor Drives
Topic: Power issue and crackling noise
Replies: 16
Views: 369

Re: Power issue and crackling noise

Having another battery would be a good test but I assume you don't have one.

Can you post a picture of the battery connection? It sounds like possibly there is a bad connection inside the battery around the connector. You may need to try disassembling that part of the battery and look inside.
by fechter
Mar 24 2020 9:21am
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1017
Views: 86519

Re: APL's DIY axial-flux motor

In the design shown, the stator core would need to be laminated to avoid being a one turn short.
by fechter
Mar 24 2020 12:10am
Forum: E-Vehicles General Discussion
Topic: C Cab Hot Rod Power Advice
Replies: 354
Views: 16576

Re: C Cab Hot Rod Power Advice

What happened to the Alien lights?

Maybe next time...
by fechter
Mar 23 2020 10:50am
Forum: E-Bike Non-hub Motor Drives
Topic: Power issue and crackling noise
Replies: 16
Views: 369

Re: Power issue and crackling noise

Angry Bob is a known troll. You can ignore his bad manners. The crackling noise is interesting. I haven't come across that one before. The symptoms indicate a bad connection somewhere between the battery and the motor. If the crackling noise is due to arcing, there will be a visible burn mark somewh...
by fechter
Mar 23 2020 10:16am
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 1692
Views: 118555

Re: la Nina rears her ugly head

Rain keeps dodging my area. It was supposed to rain yesterday, but it was a beautiful partly cloudy day. I went out for a ride and could see some dark clouds way off in the distance. Nice to get out anyway.

San Francisco Bay in the background:
Img_1570A.jpg
Img_1570A.jpg (129.32 KiB) Viewed 145 times
by fechter
Mar 22 2020 9:30pm
Forum: E-Bike Technical
Topic: throttle with yellow wire gives swapped action?
Replies: 5
Views: 109

Re: throttle with yellow wire gives swapped action?

monster wrote:
Mar 22 2020 12:46pm
Yes it seems there are some old throttles out there with the throttle hall sensor flipped over and a yellow instead of black wire.

If you hook them up to a regular controller it goes WOT 😧
That could be exciting. Glad you got it sorted out.
by fechter
Mar 22 2020 10:11am
Forum: E-Bike Technical
Topic: throttle with yellow wire gives swapped action?
Replies: 5
Views: 109

Re: throttle with yellow wire gives swapped action?

You might have the wires crossed. With the throttle disconnected, you can use a meter to measure the throttle wires coming from the controller. The negative (ground) wire will be connected to the battery negative (use ohmmeter to find). The signal line will generally measure 10k - 20k ohms against g...
by fechter
Mar 22 2020 10:04am
Forum: Battery Technology
Topic: Help me troubleshoot this pack please. How are these voltages?
Replies: 50
Views: 827

Re: Help me troubleshoot this pack please. How are these voltages?

After i fully charged the pack (cell 11=4.04v) and waited one day, cell 11 dropped to 4.00v (compared to highest cell voltage of 4.13v). So i balanced cell 11 to 4.13v and after one day, it dropped to 4.06v. The other cells have held their voltage for two days (one cell dropped 0.02v which should b...
by fechter
Mar 22 2020 9:58am
Forum: E-Bike General Discussion
Topic: A2B Octive/Metro purchase?
Replies: 52
Views: 1255

Re: A2B Octive/Metro purchase?

There are lots of them out there [for sale] if you look long enough Fechter, if I swapped-in some good street tires, what is the fastest top speed for a frame like this? 30-MPH perhaps? I'm occasionally doing 30-MPH on a beach cruiser frame (yikes!) Mine does 35 on a slight downhill. Seems very sta...
by fechter
Mar 19 2020 7:03pm
Forum: Alternative Energy
Topic: Why charge controller didnt stop
Replies: 10
Views: 230

Re: Why charge controller didnt stop

Not sure how that model is supposed to connect, but on a similar one I had, there was an "alarm" output line you have to wire to a relay to cut the power when the limit is reached. The documentation with those is sometimes lacking.
by fechter
Mar 19 2020 7:01pm
Forum: Battery Technology
Topic: Hoverboard wont charge
Replies: 7
Views: 441

Re: Hoverboard wont charge

Good deal. Thanks for posting the solution. Lucky nothing burned up when the plug was backwards.
by fechter
Mar 19 2020 6:55pm
Forum: E-Bike General Discussion
Topic: Tire slipping
Replies: 12
Views: 297

Re: Tire slipping

Higher tire pressure usually helps. Also be sure there is no oily stuff on the rim or the tire bead.
by fechter
Mar 19 2020 9:55am
Forum: E-Bike Technical
Topic: Creaking bottom bracket: anti-seize?
Replies: 6
Views: 257

Re: Creaking bottom bracket: anti-seize?

The creaking might be coming from where the cranks attach to the BB shaft. Make sure those and the pedals are tight.
by fechter
Mar 19 2020 9:52am
Forum: E-Bike Technical
Topic: Phase Amps vs Battery Amps
Replies: 18
Views: 447

Re: Phase Amps vs Battery Amps

Another way to look at it is the power will be volts x amps. When the phase amps are greater than the battery amps, it's because the motor is under load and not spinning at full speed, so the voltage across the motor will be less than the battery voltage. The battery (amps x volts) will always be sl...