Search found 17 matches

by drbenjamin
Jun 10 2019 8:46pm
Forum: E-Bike Reviews & Testing
Topic: Cycle Analyst V3 preview and first beta release
Replies: 4498
Views: 710397

Re: Cycle Analyst V3 preview and first beta release

danielrlee wrote:
Jun 10 2019 2:18am

The change was made in order to reduce precious EPROM usage. Unfortunately, there is no way to revert to the previous behavior without a firmware downgrade.
Rats. OK, thanks for the reply!
by drbenjamin
Jun 09 2019 9:03pm
Forum: E-Bike Reviews & Testing
Topic: Cycle Analyst V3 preview and first beta release
Replies: 4498
Views: 710397

Re: Cycle Analyst V3 preview and first beta release

Hi All I'm setting up my new ebike w/ a CA. I got everything working great using the Aux input (a potentiometer) to control the power limit during PAS. I am now trying to set up a preset to use the pot as a speed limiter (have the CA keep constant spped by varying power). From reading the docs on Gr...
by drbenjamin
Jun 05 2019 3:03pm
Forum: Battery Technology
Topic: Samsung 30Q - high drain 18650 Li-ion cell's capacity test
Replies: 30
Views: 1681

Re: Samsung 30Q - high drain 18650 Li-ion cell's capacity test

If you look at the discharge curve you'll notive that it is NOT LINEAR, and it differs dependent on discharge current. So you need to take your discharge current, choose the appropriate curve and check where it is for 20% or 600mA left. This is under load though. If you take the lowest discharge cu...
by drbenjamin
Jun 04 2019 1:24pm
Forum: Battery Technology
Topic: Samsung 30Q - high drain 18650 Li-ion cell's capacity test
Replies: 30
Views: 1681

Re: Samsung 30Q - high drain 18650 Li-ion cell's capacity test

So does a 2.5V discharge cutoff mean that a 14S pack can be used down to 39.8V and still be at 20%? (4.2-2.5 = 1.7V/cell total capacity, 0.34V = 20% capacity. 2.5V x 14 = 35V at cutoff, .34x14 = 4.*V for 20% residual capacity) Asking because 42V seems to be a default LVC for 14S and that would be 30...
by drbenjamin
May 29 2019 2:40pm
Forum: E-Bike General Discussion
Topic: Grin trip simulator core temp
Replies: 10
Views: 490

Re: Grin trip simulator core temp

The point of the application isn't really to model a long distance ebike trip and predict how everything will behave in a real world ride. The intention of it is to be a learning tool to understand the ramifications of different usage patterns and motor/controller/battery options in very specific s...
by drbenjamin
May 29 2019 12:35pm
Forum: E-Bike Technical
Topic: 2019 Motor Simulator, Mid-drives and other updates
Replies: 50
Views: 4224

Re: 2019 Motor Simulator, Mid-drives and other updates

Justin

Just want to take the opportunity to thank you for all you've contributed to the ebike community. The motor simulator (and the trip simulator) were invaluable to me in selecting components for my 1st ebike. As well as this forum!

Thanks so much -
by drbenjamin
May 22 2019 3:56pm
Forum: Battery Technology
Topic: 14s2p Minicube w/ 21700 batteries
Replies: 5
Views: 392

Re: 14s2p Minicube w/ 21700 batteries

Thanks - that was what I was thinking. Hopefully there will be a high discharge 21700 cell in the future, I love the small size of the minicube but would also like a little more capacity. This battery is close, but not suitable for a hill climber.
by drbenjamin
May 22 2019 1:08am
Forum: E-Bike Reviews & Testing
Topic: Cycle Analyst V3 preview and first beta release
Replies: 4498
Views: 710397

Re: Cycle Analyst V3 preview and first beta release

Pls disregard this post, I have figured out how to use the potentiometer in CAV3
by drbenjamin
May 21 2019 2:30pm
Forum: Battery Technology
Topic: Small 36V battery recommendations
Replies: 7
Views: 455

Re: Small 36V battery recommendations

I ordered a 52V from electrifybike and so far so good.


electrifybike is the webstore for a Utah eBike shop called PoweredRide that seems to be legit - you can find some reviews on PoweredRide if you Google
by drbenjamin
May 19 2019 11:23pm
Forum: Battery Technology
Topic: 14s2p Minicube w/ 21700 batteries
Replies: 5
Views: 392

14s2p Minicube w/ 21700 batteries

I spotted this from UPP tonight: https://www.ebay.com/itm/UPP-Portable-Pocket-Battery-52V-10Ah-Samsung-50E-21700-Lithium-Battery-Pack/254227423546 It's a 52V 10AH battery based on the Samsung 50E 21700. Curious what people think - these batteries have a higher capacity but lower current rating than ...
by drbenjamin
Apr 29 2019 9:25pm
Forum: E-Bike General Discussion
Topic: Grin trip simulator core temp
Replies: 10
Views: 490

Re: Grin trip simulator core temp

The temps were all at 21 and I selected MAC 12T from the pulldown menu, didn't change any parameters. Looking at them though, I see that eddy currents are non zero and also hysteresis torque. I would think that in a geared hub (with clutch) these terms should be zero when no current is flowing into ...
by drbenjamin
Apr 29 2019 9:26am
Forum: E-Bike General Discussion
Topic: Grin trip simulator core temp
Replies: 10
Views: 490

Re: Grin trip simulator core temp

Thanks amberwolf. I'm thinking that maybe the MAC is being modeled as a direct drive here - note that in the 1st mile which is all downhill there's still a temp rise, so I don't think that battery power is accounting for the temp rise. If I raise the speed limit high enough the battery starts to be ...
by drbenjamin
Apr 29 2019 12:00am
Forum: E-Bike General Discussion
Topic: Grin trip simulator core temp
Replies: 10
Views: 490

Grin trip simulator core temp

All trying to decide between a Mac 12T and a BBSHD for my commuter setup. I tried out the Grin trip simulator on their site (which is very cool) and got a surprising result - see below. A long part of my ride is along a river, and I don't expect to use any power there. I set the speed limit to refle...
by drbenjamin
Apr 26 2019 1:54pm
Forum: E-Bike Technical
Topic: 12T MAC motor and high current
Replies: 28
Views: 4734

Re: 12T MAC motor and high current

Appreciate the thread - I have a 12T Mac kit coming from em3ev (30A 9 FET controller) that I'll be putting in a 700C wheel. A little concerned about heating, so here are a couple of questions 1) "steep" is a bit subjective in describing hills. I live on top of a 400' hill, the road up is ~0.4 mi of ...
by drbenjamin
Sep 14 2015 10:06pm
Forum: E-Bike General Discussion
Topic: 1st build, advice appreciated!
Replies: 5
Views: 507

Re: 1st build, advice appreciated!

Thanks bowl, I had run across those watt meters. My only hesitation was that they're 1/2 the cost of a Cycle Analyst which seems like a much more capable device. Given that you can use those around the house to find energy hogs, maybe I'll take the plunge. It's mostly for her, to avoid her being 15 ...
by drbenjamin
Sep 14 2015 7:10pm
Forum: E-Bike General Discussion
Topic: 1st build, advice appreciated!
Replies: 5
Views: 507

1st build, advice appreciated!

All Building my 1st eBike, I've spent months reading the forums and am just about ready to order. Would appreciate advice/comments on my plans. I read (and hopefully followed!) the sticky on getting advice :D I am an avid cyclist, This bike is for my wife who would like to join me on long distance r...
by drbenjamin
Sep 12 2015 10:51pm
Forum: Battery Technology
Topic: Another No Solder/Weld 18650 Build (Updated 03/09/2014)
Replies: 344
Views: 63657

Re: Another No Solder/Weld 18650 Build (Updated 03/09/2014)

Any progress on a simple approach to the spacer bars? I'd love to build one of these, and may try hand tapping some holes in the end of 1/4" rods if needed! Also, you indicated in your OP that the Poron foam is compressed 25%, and later on in the thread linked to a McMaster part number that is 1/16"...