Search found 767 matches

by jag
Oct 23 2011 9:59pm
Forum: Battery Technology
Topic: Dewalt A123 BMS battery interface solution
Replies: 121
Views: 52028

Re: Dewalt A123 BMS battery interface solution

Jag that looks like a nice solution, but the current output from the FET driver is usually 20-25amps. Need to find one with a higher rating to make full use of the current. I've never used these, but isn't the resistance a little high? The 25 amp version has a 5 ohm value at 25'C. I think the Toroi...
by jag
Oct 22 2011 3:14pm
Forum: Battery Technology
Topic: Dewalt A123 BMS battery interface solution
Replies: 121
Views: 52028

Re: Dewalt A123 BMS battery interface solution

Update, looking for a suitable inductor. The one I found, I wasn't happy with the wire gauge, so I looked around and found a ferrite toroid, and started wrapping wire around it. I ran out of wire, but felt it would be good enough for the test. Worked better than I expected. It just goes in between ...
by jag
Sep 28 2011 10:40am
Forum: E-Bike General Discussion
Topic: Rear Hub Motor + Baby/Child Trailer possible?
Replies: 10
Views: 4272

Flipped Trailer + Child today. Trailer bruised, Child ok.

Today biking on my way to daycare with my 2year old I suddenly heard a bonk and then a scraping dragging sound. Looked back and trailer + kid was not on the wheels anymore but being dragged along on the side. I had hit a bump only a few inches tall, but that was enough to flip the trailer. Speed was...
by jag
Sep 26 2011 11:14pm
Forum: E-Bike Non-hub Motor Drives
Topic: Any decent controller for big RC motors?
Replies: 18
Views: 2634

Re: Any decent controller for big RC motors?

Current ripple will increase as the supply voltage increases, with RPM and load held constant. The motor is always running no-load, so at constant RPM the load will be the same and thus the average motor current will be the same. However, when the battery voltage increases the ripple will be larger...
by jag
Sep 26 2011 1:16pm
Forum: E-Bike Non-hub Motor Drives
Topic: Any decent controller for big RC motors?
Replies: 18
Views: 2634

Re: Any decent controller for big RC motors?

OK, I have found a few spare minutes and did the test. And the results are... http://i.imgur.com/sEYZr.png Hz is phase frequency, measured on hall sensor (can be converted to RPM). V - battery voltage. Test done with cheap chinese controller and Turnigy CA120 motor. Measurements include relatively ...
by jag
Sep 26 2011 1:02pm
Forum: Battery Technology
Topic: Discharging all cells to lvc with LiPo charger?
Replies: 10
Views: 965

Re: Discharging all cells to lvc with LiPo charger?

Also, acording to the manual, the 106b can discharge cells when hooked up to an external battery source, [NOT a power supply} That's why I have been unable to discharge and break in my Lipo. I only have power supply for source voltage. The charger discharges the cells by dumping the power back into...
by jag
Sep 26 2011 12:24am
Forum: Battery Technology
Topic: Discharging all cells to lvc with LiPo charger?
Replies: 10
Views: 965

Re: Discharging all cells to lvc with LiPo charger?

It cuts when the first cell hits LVC. This enables you to capacity test the entire pack to see how weak the weakest cell is. This is indeed good for packs, but not as good when one has a lot of cells to capacity match before putting into packs. Then it would be nice to have the complete graph from ...
by jag
Sep 25 2011 11:52pm
Forum: Battery Technology
Topic: Discharging all cells to lvc with LiPo charger?
Replies: 10
Views: 965

Discharging all cells to lvc with LiPo charger?

I've been looking to get something like an iCharger to capacity test cells though charge/discharge cycles. I was wondering if a charger like the iCharger 106b actually discharges all 6 cells to lvc, or simply cuts when the first cell hits lvc? (So I get the full discharge curve for the weakest cell,...
by jag
Sep 13 2011 12:22am
Forum: E-Bike Technical
Topic: Installing 220V in the garage to charge FASTER
Replies: 61
Views: 6284

Re: Installing 220V in the garage to charge FASTER

if you currently have a 12 AWG copper circuit running to the garage you can convert it from 120 to 240V at the junction box with the duplex outlets. first isolate the circuit so you know which boxes are on that circuit. pull all the duplex outlets out of the wall first that will convert to 120V. on...
by jag
Sep 11 2011 3:13pm
Forum: General Discussion
Topic: The Economist on measures for safe cycling.
Replies: 7
Views: 725

The Economist on measures for safe cycling.

There's always been a debate if bikes belong on the road with the traffic or not. Some prominent cyclist such as Forrester in his "Effective cycling" book argued that bikes are vehicles and with proper cycling the road is the best place. However, as The Economist argues below actual statistics favor...
by jag
Sep 05 2011 10:04pm
Forum: Motor Technology
Topic: The One True Alter-motor
Replies: 17
Views: 12010

Re: The One True Alter-motor

http://en.wikipedia.org/wiki/BAS_Hybrid#Generation_II_BAS_.28eAssist.29 From same wikipedia page: According to the EPA the 2009 Saturn Vue BAS hybrid garners an improvement of 32% city (19>25mpg) and 24% highway (26>32mpg) making the combined economy improvement 27% (22>28mpg) over the base 4cyl FW...
by jag
Sep 03 2011 12:57pm
Forum: General Discussion
Topic: Streetlife on bikes in Toronto (movie review:Monkey Warfare)
Replies: 0
Views: 389

Streetlife on bikes in Toronto (movie review:Monkey Warfare)

Dan and Linda are ex leftist revolutionaries in their 40's. They now live a quiet life biking around Toronto, collecting gems from garage sales and dumpsterdiving to resell on the Internet, fixing bikes in their basement to sell upmarket to rich people who pay dearly for retro when the chrome is pol...
by jag
Aug 30 2011 11:44pm
Forum: E-Bike Non-hub Motor Drives
Topic: Acid test - Mountain Climb- 3220 motor hv160
Replies: 104
Views: 9093

Re: Acid test - Mountain Climb- 3220 motor hv160

I didn't find gearing info in your thread. Like Miles said this is crucial. Looking at the pics I was guessing you have an 80tooth rear, I'm assuming a 13 tooth on the jackshaft, and a 3:1 belt giving 18:1 total reduction. This seems suitable for your goal of going 70km/h or so (corresponds to just ...
by jag
Aug 30 2011 9:47pm
Forum: E-Bike General Discussion
Topic: Hub motor hydraulic caliper clearance
Replies: 28
Views: 6367

Re: Hub motor hydraulic caliper clearance

Hi there, whats the full name of the Hayes brake that does fit? Cheers. I've had Hayes 9 on one of my bikes, with an X5. The fit is very tight, needs disc spacers about half a mm. The Hayes caliper worked well for a while, then seized during the winter, due to corrosion from the melting salt. I hav...
by jag
Aug 19 2011 6:33pm
Forum: E-Bike General Discussion
Topic: Persecuting E-Bikes in New York City
Replies: 220
Views: 23707

Re: Persecuting E-Bikes in New York City

I think the most important point in the article to cite are: http://www.reuters.com/article/2011/06/17/idUS129554523420110617 In the tri-state region of the includes New Jersey, downstate New York and Connecticut pedestrian fatalities average 415 deaths per year. Presumably, most of those fatalities...
by jag
Aug 17 2011 9:32pm
Forum: E-Bike Technical
Topic: Belt Drives; Better for E-bikes? Gates has one.
Replies: 38
Views: 4059

Re: Belt Drives; Better for E-bikes? Gates has one.

I have a Gates belt drive on my GT. The bike in my avatar. Its ok, but does have its pitfalls. First, it likes to jump the track occasionally. Second, changing the tire is a nightmare. Lastly, I have not been able to source a single new belt. Plenty of kits with all the gears and crap... I've calle...
by jag
Aug 07 2011 1:12pm
Forum: General Discussion
Topic: Perspective: A free, user on-line community v.s. commercial
Replies: 3
Views: 611

Perspective: A free, user on-line community v.s. commercial

The fate of ES is still in turmoil. A person unknown to the ES community bought the ES from longtime list maintainer Knightmb. Trevor intended to monetize the site, but members rebelled. Trevor realized he got in way over his head and everything points toward that the ES members and mods will take b...
by jag
Apr 28 2011 6:10pm
Forum: E-Bike Non-hub Motor Drives
Topic: Understanding Gearing via V4 Reduction Drive
Replies: 17
Views: 1944

Re: Understanding Gearing via V4 Reduction Drive

SHiFT, You've pretty much solved this yourself. Bicycle gearing reduces torque to gain speed (generally). Motor gearing reduces speed to gain torque. So, by copying your bicycle gearing for the second stage you're going 4 steps forward then 2 steps back :) "4 steps forward and 2 steps back" capture...
by jag
Apr 27 2011 8:59pm
Forum: Alternative Energy
Topic: Who killed american solar?
Replies: 17
Views: 3157

Who killed american solar?

We saw "Who killed the electrical car". This month Canadian business ran an article "Who killed American solar? " Turns out solar hot water heating was "hot" business in the American south from around 1900 to 1950 with manufacturers in CA and FL. In 1891 a single home solar water heating unit cost $...
by jag
Apr 25 2011 9:15pm
Forum: E-Bike General Discussion
Topic: BMC/MAC 72v 30amp vs HT3525 72v 60a
Replies: 20
Views: 2461

Re: BMC/MAC 72v 30amp vs HT3525 72v 60a

Seens like a BMC that can handle 1.7kw peaks at 30 amps is almost on par with HT3525 running 60 amps, torque wyse. Is the simulator right? Am I missing Something? What you guys think? Geared hub for a comutter bike and DD for big power numbers? Pretty much sums it up. DD hubs are for those who want...
by jag
Apr 24 2011 9:40pm
Forum: E-Bike Non-hub Motor Drives
Topic: Bafang Fun8 Motor with belt setup
Replies: 7
Views: 1781

Re: Bafang Fun8 Motor with belt setup

Nice work with the re-engineering of the bafang motor, belt transmission and housing for everything. I wonder what the advantage would be of hacking into and modding a Bafang compared to buying an RC outrunner of similar diametre. For quietness just run at low rpm. Should give similar torque (or mor...
by jag
Apr 23 2011 11:52pm
Forum: E-Vehicles General Discussion
Topic: Smart/Cellphone GPS for navigation
Replies: 3
Views: 436

Re: Smart/Cellphone GPS for navigation

My experience: iPhone + google maps: turns useless in many situation where either GPS loses signal or data speed/connection is too slow/crappy to keep loading maps. Nokia: Navigation functionality and user interface leaves a lot to be desired. The real GPS companies such as Garmin and Tomtom have wa...
by jag
Apr 21 2011 2:32pm
Forum: General Discussion
Topic: How much solar power could buy for $2,000?
Replies: 30
Views: 2355

Re: How much solar power could buy for $2,000?

So what I'm getting at is, your family doesn't have to run everything at once. Except we do need that capability... Put dinner in the oven and then say the fridge, chest freezer and hot water heater all kick on at the same time. Oh and someone just used the bathroom so the well-pump kicked on too. ...
by jag
Apr 19 2011 10:29pm
Forum: General Discussion
Topic: How much solar power could buy for $2,000?
Replies: 30
Views: 2355

Re: How much solar power could buy for $2,000?

REdiculous Nice try but that's a fail... I see the thread subject line is "How much solar power could buy for $2,000?" (what is it your reading ? something far different as I understand it now) thats what I set out to show.. How much of a change is needed to work with $2000.. obviously not many peo...
by jag
Apr 19 2011 1:51pm
Forum: General Discussion
Topic: How much solar power could buy for $2,000?
Replies: 30
Views: 2355

Re: How much solar power could buy for $2,000?

mdd0127 for president! Governments and administrations are full of people yakking about problems and solutions none of them have any hands on experience with. A recent graduate from our school came back and gave a talk about how he built a net-zero home. That is a home that on average generates all ...