Search found 12589 matches

by fechter
Nov 21 2018 1:39pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 2590
Views: 136449

Re: Sur-Ron - New Mid drive Bike

madin88 wrote:
Nov 21 2018 12:41pm

What was the no-load speed of the 60V surron (in kmh)?
d
I was seeing around 72kph (45mph). The battery was about 50%, right around 60v.
by fechter
Nov 21 2018 12:11pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 2590
Views: 136449

Re: Sur-Ron - New Mid drive Bike

Thats around 700W of no-load consumption which would be indeed pretty high. I wonder how that compares to something similar. What does a Zero draw with the wheel up? With that much waste heat, something should be getting pretty warm, but I never feel the motor or controller getting more than barely...
by fechter
Nov 21 2018 12:06pm
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 982
Views: 41028

Re: la Nina rears her ugly head

Actually raining here now. Not heavy, but I'll take whatever I can get. This should help put out the fires.
by fechter
Nov 21 2018 9:20am
Forum: Battery Technology
Topic: Do I need diodes with this layout?
Replies: 17
Views: 459

Re: Do I need diodes with this layout?

One thing though -- with the pre-charge resistors in place as shown in the updated diagram, won't that send a small amount of power to the DC-DC converter? Seems wasteful. I'm thinking the pre-charge resistors should be on a momentary switch which I would engage just prior to turning the key (not u...
by fechter
Nov 21 2018 9:11am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 2590
Views: 136449

Re: Sur-Ron - New Mid drive Bike

I finally got some instrumentation installed on mine: Img_0964.jpg Cycle Analyst is tied in now, but only measures the current going to the controller and not the dc-dc converter. I found the switched pack voltage line coming from the key and picked up one of the hall sensor signals for speed. I'm s...
by fechter
Nov 20 2018 3:23pm
Forum: Large EV General Discussion
Topic: Tesla MS-MX refresh coming in April?
Replies: 3
Views: 69

Re: Tesla MS-MX refresh coming in April?

Does that mean there will be a bunch of used Tesla packs up for grabs?
by fechter
Nov 20 2018 3:17pm
Forum: Battery Technology
Topic: Dell Laptop Battery Charger for E-Bike (Renamed Thread from cc/cv)
Replies: 13
Views: 218

Re: Normal non cc/cv PSU with a normal cc/cv charger to increase volts and still get cc/cv charge to battery

One thing to keep in mind is the required voltage swing through the charging cycle. The unit with CC/CV needs to accommodate the entire voltage swing. For example, a 52v (14s) pack might go as high as 58.8v at end of charge. If the cells were discharged to 3v/cell, that would be starting out at 42v....
by fechter
Nov 20 2018 3:10pm
Forum: E-Vehicles General Discussion
Topic: Regen braking edge case - pusher trailer, mountain range
Replies: 1
Views: 42

Re: Regen braking edge case - pusher trailer, mountain range

There's a few out there. One I remember used a Bob trailer with a direct drive hub motor. Any DD hub motor can do regen with the right controller. Here's one, but there are more https://www.endless-sphere.com/forums/viewtopic.php?t=49207 More ideas here: https://electricbikereport.com/electric-cargo...
by fechter
Nov 20 2018 2:52pm
Forum: Items for Sale - New
Topic: JP spot welder
Replies: 1122
Views: 137476

Re: JP spot welder

1. You can use standard 12V ac/dc adapter with 5.5/2.1 mm barrel connector (most common one), 500 mA is fine, maybe even less, but I haven' tried. It's polarity will be marked, it's standard negative outer, and inner pin is positive. There is a diode on the input so nothing will happen if you accid...
by fechter
Nov 20 2018 8:48am
Forum: Battery Technology
Topic: Do I need diodes with this layout?
Replies: 17
Views: 459

Re: Do I need diodes with this layout?

I've never seen a contactor with a 100 volt rated coil... It would be possible to use a contactor with a 12v coil and run it off the DC-DC converter. It might be good to put a diode across the contactor coil (reverse biased) if it doesn't have one built-in. The diode catches the voltage spike when ...
by fechter
Nov 20 2018 8:36am
Forum: Alternative Energy
Topic: How much power to field coils?
Replies: 19
Views: 258

Re: How much power to field coils?

The slip rings go to the field coil, so you can trace the wires going to them. Use an ohmmeter and measure the resistance of the field coil and you can calculate the current. Car alternators I've messed with before took around 2A at 12V for the field winding. They would normally run at less than this.
by fechter
Nov 20 2018 8:24am
Forum: E-Bike Technical
Topic: How to build a brake light?
Replies: 9
Views: 189

Re: How to build a brake light?

So, I need to build another circuit directly from battery to have enough power to power on a simple LED ? Most likely. The voltage regulator in the controller is very limited and already has some load on it. You might get away with 20mA. If you want a brighter brake light, you will need some kind o...
by fechter
Nov 20 2018 12:13am
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 982
Views: 41028

Re: la Nina rears her ugly head

el nino 2018.JPG
el nino 2018.JPG (58.93 KiB) Viewed 19 times
by fechter
Nov 19 2018 4:00pm
Forum: E-Bike Non-hub Motor Drives
Topic: IT'S ALIVE...... BBS02HD!!
Replies: 13
Views: 462

Re: IT'S ALIVE...... BBS02HD!!

Any idea if the metal gear made for the BBSHD will fit in the BBS02? Plastic gear meltdowns were pretty common on the BBS02.
by fechter
Nov 19 2018 3:55pm
Forum: Motor Technology
Topic: searching for legalisation documentation zero s 2014 driveline
Replies: 4
Views: 82

Re: searching for legalisation documentation zero s 2014 driveline

The EMI data is only going to valid for the exact same configuration, including all the wiring, batteries, accessories, etc.
The same exact parts and wires laid out differently will have different results.
Unless you are planning to sell these, I don't think EMI testing is required.
by fechter
Nov 19 2018 3:45pm
Forum: Motor Technology
Topic: BLDC dead time
Replies: 1
Views: 60

Re: BLDC dead time

Good question. Most of the ones I have put on a scope don't appear to have dead time between commutation changes. As long as you don't let the complimentary pairs shoot through, seems like it should be OK. Spikes during commutation should not be any bigger than what you get when it's PWM switching. ...
by fechter
Nov 19 2018 3:39pm
Forum: Battery Technology
Topic: Ready to spot weld. Please check my work!
Replies: 6
Views: 179

Re: Ready to spot weld. Please check my work!

For the end collectors, you could cut one of the nickel sheets in half lengthwise and solder a heavy copper (10ga) wire across it. I like to avoid soldering heavy wire directly to the cells. You could bend the sheet so the wire sits above the plane of the cell tops if that fits your enclosure better...
by fechter
Nov 19 2018 12:44pm
Forum: Stand-up E-scooters and E-skateboards
Topic: Currie Kick Scooter conversion
Replies: 285
Views: 26907

Re: Currie Kick Scooter conversion

I'm thinking here...so an MX650 with this motor...is 60-70kw too much? Too much is not enough... :twisted: That sure does look like a beast. OK, maybe a little overkill for a standup scooter. I'd go for something you can sit on and be sort of attached to so you don't get left behind. You could make...
by fechter
Nov 19 2018 12:27am
Forum: Stand-up E-scooters and E-skateboards
Topic: Ideal scooter specs, does this exist? Or will it be diy?
Replies: 16
Views: 485

Re: Ideal scooter specs, does this exist? Or will it be diy?

I have been doing a lot of research also with similar requirements as you. I think this one will be a good fit for you. As you are located in San Francisco, they are located in San Rafael. Spoke to them on the phone, they seemed very nice and have a service department for repairs. Check it out. htt...
by fechter
Nov 18 2018 10:39pm
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 982
Views: 41028

Re: la Nina rears her ugly head

Now it's finally getting interesting: Tuesday Night Rain, mainly after 4am. The rain could be heavy at times. Low around 54. South wind around 8 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible. Wednesday Rain before 10am, then showers aft...
by fechter
Nov 16 2018 1:29pm
Forum: E-Bike General Discussion
Topic: Test speed controller while awaiting throttle
Replies: 9
Views: 153

Re: Test speed controller while awaiting throttle

I thought most of the speed controllers ran on a 1-4V range. So if you apply MORE than 4 volts (shorting the wires as you suggested) it would still run at full throttle? Or are they set to somehow ignore anything over 4? And I am pretty sure that controller was dead before I started hammering, thus...
by fechter
Nov 16 2018 10:27am
Forum: E-Bike General Discussion
Topic: Help magnets in hub motor
Replies: 21
Views: 454

Re: Help magnets in hub motor

Interesting! Have you run across any articles that talk about this effect in detail? I bet going from N35 to N45 might add a little more kv's to a motor, but not like going from weak ceramics to strong magnets. I'm sure there are articles out there, but I haven't looked. There must be a way to do t...
by fechter
Nov 15 2018 1:13pm
Forum: E-Bike General Discussion
Topic: Help magnets in hub motor
Replies: 21
Views: 454

Re: Help magnets in hub motor

Why does stronger magnets increase the motor Kv if that's what is happening? It ought to just make for stronger attraction/repulsion and therefore more torque, but no speed change in my thinking. Stronger magnets generate more BEMF at a given speed, so will equal the pack voltage at a lower RPM. Pr...
by fechter
Nov 15 2018 9:27am
Forum: E-Bike Technical
Topic: Battery builder concerned over building a Luna Mighty Mini Clone
Replies: 8
Views: 169

Re: Battery builder concerned over building a Luna Mighty Mini Clone

Another factor is if your commute is short enough, the batteries won't have time to get overheated.
by fechter
Nov 15 2018 12:24am
Forum: E-Scooter and Motorcycle Photos & Videos
Topic: Euroscooter to drift trike.
Replies: 10
Views: 191

Re: Euroscooter to drift trike.

The hub that came with the new euro scooter does not turn easily by hand. I hooked it up to a speed controller and it will turn, but not smoothly at all. I took the side of the hub off to see if there is any rust, but it seems like it is all pretty clean. What mechanically do I need to look for tha...