Search found 10230 matches

by spinningmagnets
Mar 20 2019 6:24pm
Forum: Battery Technology
Topic: Echo 58v and Greenworks 60v in parallel
Replies: 3
Views: 57

Re: Echo 58v and Greenworks 60v in parallel

Echo and EGO both use 14 cells in series, regardless of the 56V / 58V names. They are both the same voltage for charging and also the Low Voltage Cutoff / LVC. Greenworks uses 15S, and there is a 15-cell DeWalt pack that can be used as a 5S/3P in an 18V tool, or a 15S 1P in the other 60V tool. It's ...
by spinningmagnets
Mar 20 2019 3:36pm
Forum: General Discussion
Topic: Boeing 737 Max 8 failures..an explanation ?
Replies: 27
Views: 441

Re: Boeing 737 Max 8 failures..an explanation ?

Thanks for the detailed response.
by spinningmagnets
Mar 20 2019 10:19am
Forum: General Discussion
Topic: Boeing 737 Max 8 failures..an explanation ?
Replies: 27
Views: 441

Re: Boeing 737 Max 8 failures..an explanation ?

I suppose the question now becomes...which airlines insisted on redundant AoA sensors, and which ones (like the two crashed planes) found a single vital sensor to be allowable. I am DEEPLY disappointed that Boeing would allow any plane to leave their factory with single AoA sensor as an option. As s...
by spinningmagnets
Mar 18 2019 1:39pm
Forum: E-Bike General Discussion
Topic: hub motors, have you broken your rim/spokes yet
Replies: 10
Views: 218

Re: hub motors, have you broken your rim/spokes yet

It helps to have a moped rim, because the spoke holes are angled. I have read about a surprising amount of success with one-cross spoke pattern using 12ga and 14ga spokes. The thicker 10ga do not have any stretch or flex in them, and they break more than I would have guessed. Also, rear suspension i...
by spinningmagnets
Mar 18 2019 12:46pm
Forum: General Discussion
Topic: using voltage sag as indication of bad battery
Replies: 11
Views: 167

Re: using voltage sag as indication of bad battery

In the DIY home power-wall community, there is a growing use of thermal cameras to identify a hot cell, long before a fuse might blow from an internal short.

Of course the most affordable thermal cameras are not as precise, and have a coarse resolution, but...they appear to be "good enough".
by spinningmagnets
Mar 18 2019 10:18am
Forum: Battery Technology
Topic: DIY welder almost finished but
Replies: 11
Views: 153

Re: DIY welder almost finished but

Once you have a large transformer, you can even put a few turns of smaller wire through the secondary window, and leave some airspace. It is good to tie-wrap the secondary or it will vibrate a lot, but as long as it doesn't vibrate through the wire insulation, it will still be fine. You can lower th...
by spinningmagnets
Mar 18 2019 9:32am
Forum: General Discussion
Topic: Boeing 737 Max 8 failures..an explanation ?
Replies: 27
Views: 441

Re: Boeing 737 Max 8 failures..an explanation ?

These last two years have seen historic lows in the prices of fuel, and the 737 and also the 737max were both developed during a time when there was a fear of near-future fuel prices climbing. There is a constant drive for higher efficiencies, and when more efficient engines are made, there is a des...
by spinningmagnets
Mar 18 2019 9:16am
Forum: Battery Technology
Topic: DIY welder almost finished but
Replies: 11
Views: 153

Re: DIY welder almost finished but

The total watts are determined by the copper mass passing through the transformer windows. Once they are as filled as possible, you can divide that copper mass into a few turns of fat wire (low volts/high amps)...or...more turns of smaller wire (higher volts/lower amps) https://www.electricbike.com/...
by spinningmagnets
Mar 18 2019 8:42am
Forum: Battery Technology
Topic: DIY welder almost finished but
Replies: 11
Views: 153

Re: DIY welder almost finished but

The total watts are determined by the copper mass passing through the transformer windows. Once they are as filled as possible, you can divide that copper mass into a few tons of fat wire (low volts/high amps)...or...many turns of smaller wire (higher volts/lower amps)
by spinningmagnets
Mar 18 2019 8:38am
Forum: E-Scooter and Motorcycle General Discussion
Topic: CSC City Slicker
Replies: 21
Views: 832

Re: CSC City Slicker

I believe Micah Toll did a youtube review. It's too small if you are above six feet. I seem to remember he said it wasn't bad for around town. I also seemed to remember there was a lead acid version, and a lithium version. Since this appears to have been built to a low price point, I am certain ther...
by spinningmagnets
Mar 17 2019 12:02pm
Forum: E-Bike Technical
Topic: Calculating Battery Life based on voltage
Replies: 12
Views: 214

Re: Calculating Battery Life based on voltage

I was thinking about typing something that I thought would be clever and informative, but...after reading the above posts...do what Dogman says. (*also, check his post count)
by spinningmagnets
Mar 17 2019 11:49am
Forum: Battery Technology
Topic: Scavenging one nearly new battery to make another?
Replies: 52
Views: 667

Re: Scavenging one nearly new battery to make another?

Just to let you know, IF the true "fully charged" voltage of your existing battery packs is 58V, then they can be used as a back-up power source, since many inverters that convert DC batteries to 120V AC have a 60V input max. Typically the 48V labelled packs have 13 cells in series, and the 52V pack...
by spinningmagnets
Mar 16 2019 11:01am
Forum: Battery Technology
Topic: Nissan Leaf Modules over 500 amps peak?
Replies: 19
Views: 266

Re: Nissan Leaf Modules over 500 amps peak?

Add 100-psi compression on the flat sides, and also add a temp sensor to the inner cells. 140F temps or more are a no-go, warm is good, hot is bad.

Extraordinary claims require extraordinary evidence.
by spinningmagnets
Mar 16 2019 10:58am
Forum: Motor Technology
Topic: Serious FOCer (84V VESC 6 based controller)
Replies: 13
Views: 423

Re: Serious FOCer (84V VESC 6 based controller)

I looked at a teardown of this controller just now. I like the orientation of the FETs. Someone also suggested this kind of orientation on my Cheap FOCer thread. I think I might use that sort of FET layout for a 12 FET version For about a year, the Adaptto controllers were the "next big thing", and...
by spinningmagnets
Mar 15 2019 7:03pm
Forum: Motor Technology
Topic: Serious FOCer (84V VESC 6 based controller)
Replies: 13
Views: 423

Re: Serious FOCer (84V VESC 6 based controller)

This looks like it will really provide some competition for the Adaptto Mini-E. Open source is good.
by spinningmagnets
Mar 13 2019 5:35pm
Forum: Motor Technology
Topic: Revolt RV-series motor review and comparisons
Replies: 145
Views: 6740

Re: Revolt RV-series motor review and comparisons

On the weekend of March 17, I deleted quite a few posts (on the last two pages, at the time) that were part of a discussion that devolved into an argument with a sprinkling of personal attacks. Posts that only discussed motors and electrical phenomena were left intact. Posts that were personal attac...
by spinningmagnets
Mar 09 2019 11:07pm
Forum: General Discussion
Topic: Greatest boxers of all time ?
Replies: 21
Views: 617

Re: Greatest boxers of all time ?

I don't think Tyson is a good example of a nice person, but...in his prime he was devastating. It's all armchair quarterbacking to discuss Tyson vs Ali vs Joe Louis, etc...
by spinningmagnets
Mar 09 2019 11:02pm
Forum: E-Vehicles General Discussion
Topic: ICE vs Electric Motor Transmissions
Replies: 52
Views: 1351

Re: ICE vs Electric Motor Transmissions

Some of the early car EV conversions used the stock manual transmission, and most users reported only using second gear and the top gear. Chevy is famous for their simple and robust 2-speed "Powerglide" automatic transmission. That might be an option. I agree with Luke that these are most useful in ...
by spinningmagnets
Mar 09 2019 5:18pm
Forum: E-Vehicles General Discussion
Topic: Reflections echo reflexions
Replies: 16
Views: 262

Re: Reflections echo reflexions

I only mentioned that because when someone is building a custom E-moto, there are dozens of design issues that must be compromised and a decision made. Choosing a sprocket-rotor / sprotor can be very helpful to know about to help certain builds. Knowing about an O-ring chain might make a sprotor a v...
by spinningmagnets
Mar 09 2019 5:06pm
Forum: General Discussion
Topic: Greatest boxers of all time ?
Replies: 21
Views: 617

Re: Greatest boxers of all time ?

I think if opponents are well matched in size and weight, each would do well in their trained category. In an MMA fight, the boxer is likely to lose. In a boxing match, the MMA fighter is likely to lose...just my opinion. Boxing is scored differently than MMA, and MMA usually ends in a submission (t...
by spinningmagnets
Mar 09 2019 4:50pm
Forum: E-Vehicles General Discussion
Topic: Reflections echo reflexions
Replies: 16
Views: 262

Re: Reflections echo reflexions

I had a friend who used an "O-ring chain" on a Honda 750 where each link had an ostensibly life-time amount of synthetic lube trapped around each chain pin. It was his only means of transportation. He never lubed it, and it lasted years. He stated that if it ever failed, he would get another of the ...
by spinningmagnets
Mar 09 2019 4:44pm
Forum: Battery Technology
Topic: Fuse-wire for individual cells, DIY Tesla style
Replies: 113
Views: 14596

Re: Fuse-wire for individual cells, DIY Tesla style

I recall seeing a device with several DC circuits that had a blown fuse alert. On the current input side, when the fuse would blow in the lower-resistance circuit, a short parallel circuit had a tiny bulb and a high-Ohm resistor. Normal current took the "path of least resistance". As long as the wor...
by spinningmagnets
Mar 08 2019 9:42pm
Forum: Battery Technology
Topic: Welding busbars to Nickel Strip?
Replies: 2
Views: 147

Re: Welding busbars to Nickel Strip?

A thin and narrow nickel strip is perfect for the parallel connections.

Makita laser-welds nickel-plated copper to their 30Q/25R cells.
by spinningmagnets
Mar 08 2019 3:16pm
Forum: Battery Technology
Topic: New weldless battery system crowdfunfing project
Replies: 44
Views: 1305

Re: New weldless battery system crowdfunfing project

If the causal readers take anything away from this discussion, I hope it is the fact that the negative end of an 18650/21700 cell is the connection that is the most sensitive to any heat that is used in the connection process . Conquer the negative end, and the positive is easy. I haven't found any ...
by spinningmagnets
Mar 05 2019 5:54pm
Forum: E-Bike General Discussion
Topic: Discharging a 52 volt battery pack
Replies: 7
Views: 164

Re: Discharging a 52 volt battery pack

An incandescent filament bulb will work. 40W is better than 100W, but either will work.

I recommend that you don't allow the pack to go below 3.3V per cell. 14S X 3.3V = 46V