Search found 7664 matches

by Alan B
Jun 20 2020 8:25pm
Forum: E-Bike General Discussion
Topic: RadPowerBike RadCity Commuter
Replies: 153
Views: 8748

Re: RadPowerBike RadCity Commuter

I ordered an adapter cable from Bolton ebikes so we could try upgrading the battery on this RadCity without hacking up the cables, allowing it to be easily reversed. We've already upgraded the controller with the Bolton unit which helped some with hill climbing, but we wanted to try the 14 cell 52 v...
by Alan B
Jun 20 2020 7:58pm
Forum: E-Bike General Discussion
Topic: Peugeot Canyon Express Commuter
Replies: 42
Views: 5640

Re: Peugeot Canyon Express Commuter

My son is still commuting some of the time on this ebike. The new RadCity doesn't have quite the hill climbing power of the 9C. So this is still a solid commuter.
by Alan B
Jun 06 2020 2:22pm
Forum: E-Bike General Discussion
Topic: New Build with EGO 56V Home Depot Battery - Wow
Replies: 53
Views: 14886

Re: New Build with EGO 56V Home Depot Battery - Wow

Be aware that the battery controller does not appear to disconnect the battery from the terminals. The batteries I have seen photos of have direct connections from the output terminals to the pack. In order to honor the battery controller I think you must monitor the data output. So your controller'...
by Alan B
May 20 2020 12:54pm
Forum: Battery Technology
Topic: Understanding and Using EGO Power+ Batteries
Replies: 102
Views: 36231

Re: Understanding and Using EGO Power+ Batteries

Fantastic Progress.

Thanks for your effort!

Welcome to ES!!
by Alan B
Apr 16 2020 10:38am
Forum: Battery Technology
Topic: One KiloWatt 18S Bulk Charger
Replies: 170
Views: 20339

Re: One KiloWatt 18S Bulk Charger

I've heard similar things, however there are no specs or application notes for this that I'm aware of. So we don't know what the actual limits are. Too many in series will exceed the voltage limits of some components at some point. It would be ideal to find a Meanwell app note that would contain the...
by Alan B
Apr 16 2020 8:24am
Forum: Battery Technology
Topic: One KiloWatt 18S Bulk Charger
Replies: 170
Views: 20339

Re: One KiloWatt 18S Bulk Charger

Folks, there are a number of ways to do this, and the differences are subtle but can be important. Redundant connections can cause unwanted currents to flow and unwanted voltage drops or even short circuits. Either use independent floating supplies or supply outputs and allow the series connections ...
by Alan B
Apr 14 2020 11:10pm
Forum: Battery Technology
Topic: One KiloWatt 18S Bulk Charger
Replies: 170
Views: 20339

Re: One KiloWatt 18S Bulk Charger

Yes, you can do one section at a time as long as the bike system is not grounded. This thread is about three meanwells effectively in series. Works fine, as these particular meanwells are suited for battery charging. Not all Meanwells are. They need to have floating grounds and be current and voltag...
by Alan B
Apr 14 2020 7:13pm
Forum: Battery Technology
Topic: One KiloWatt 18S Bulk Charger
Replies: 170
Views: 20339

Re: One KiloWatt 18S Bulk Charger

The ground path can connect the two charger's negative leads together, shorting out the bottom 6S section.

This is only safe if the 12S charger is totally "floating", and does not have a grounded connection.

If you don't understand what all this means then don't attempt it.

Be Safe.
by Alan B
Apr 07 2020 7:06pm
Forum: Battery Technology
Topic: Understanding and Using EGO Power+ Batteries
Replies: 102
Views: 36231

Re: Understanding and Using EGO Power+ Batteries

That would be really excellent. Looking at the parts count in the BMS it doesn't appear to be a low chip count wonder. There are a lot of parts in there.
by Alan B
Mar 07 2020 11:00pm
Forum: E-Bike Technical
Topic: 60 volt vs 72 volt
Replies: 84
Views: 8957

Re: 60 volt vs 72 volt

Powervelocity Controllers use Sinusoidal Commutation, not FOC (Field Oriented Control). The Sabvoton that I have is FOC as are the PhaseRunners. There's a world of difference in the way they generate sinewaves and in the feature sets they offer. https://www.motioncontroltips.com/faq-whats-the-differ...
by Alan B
Mar 07 2020 10:45pm
Forum: Motor Technology
Topic: maxing out phase amps
Replies: 22
Views: 3215

Re: maxing out phase amps

Justin has measured saturation on a number of motors, there's an old thread on the subject. http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=14494 It's hard to saturate a motor instantly due to the inductance of the winding, unless you have infinite voltage to drive it with. Justin found it ...
by Alan B
Mar 07 2020 9:56pm
Forum: General Discussion
Topic: World Domination, I just got my self a 3d Printer!!!
Replies: 642
Views: 76907

Topeak Trunk Risers

Sometimes we want to use a Topeak trunk with some regular saddlebags. The trunk has some small fold-out saddlebags but they aren't very large or heavy duty. Unfortunately the trunk sits too low and the saddlebags need more room to clip to the bars. So I whipped up a variation of my earlier design to...
by Alan B
Nov 15 2019 10:45am
Forum: E-Bike Non-hub Motor Drives
Topic: Diamondback OverDrive 27.5 "RidgeRunner"
Replies: 69
Views: 19000

Re: Diamondback OverDrive 27.5 "RidgeRunner"

I saw the announcement about the bridge. Very interesting.

I recall reading about Eric of Lunacycle riding across the Golden Gate bridge at night during a big storm. Quite the adventure.
by Alan B
Oct 29 2019 7:18pm
Forum: E-Bike General Discussion
Topic: Does torque normally change with battery voltage?
Replies: 30
Views: 2488

Re: Does torque normally change with battery voltage?

Working with closed systems is so frustrating. Hence one reason most folks on ES use DIY or modified setups. I think undercharging the battery to make it last longer is silly. Use it. After several years of use replace it. Hobbling an already marginal system is not worthwhile, in my opinion. The onl...
by Alan B
Oct 29 2019 7:06pm
Forum: E-Bike General Discussion
Topic: Does torque normally change with battery voltage?
Replies: 30
Views: 2488

Re: Does torque normally change with battery voltage?

OK no time now, will parse later see if specific answers are there to see if my understanding is better. You have to model your actual data to get specific useful predictions. Generalizations don't get you there, even if they are all correct for some situations. Well when choosing and sourcing the ...
by Alan B
Oct 29 2019 5:00pm
Forum: Battery Technology
Topic: Understanding and Using EGO Power+ Batteries
Replies: 102
Views: 36231

Re: Understanding and Using EGO Power+ Batteries

PETG is a good choice. I haven't tried TPU yet, have heard it can really bond to the PEI and create problems. PETG bonds pretty well to PEI as well, damaged one build plate that way.
by Alan B
Oct 29 2019 4:39pm
Forum: E-Bike General Discussion
Topic: Does torque normally change with battery voltage?
Replies: 30
Views: 2488

Re: Does torque normally change with battery voltage?

You have to model your actual data to get specific useful predictions. Generalizations don't get you there, even if they are all correct for some situations. You need enough voltage to: 1) overcome back EMF for the speed you are going and have enough voltage left to both: 2) overcome resistive losse...
by Alan B
Oct 29 2019 9:41am
Forum: E-Bike General Discussion
Topic: Does torque normally change with battery voltage?
Replies: 30
Views: 2488

Re: Does torque normally change with battery voltage?

It's not like I want to climb that hill at 25km/hr. So, if back EMF limitting the current isn't the issue reducing torque, there has to be something else on my bike reducing the current at lower battery voltage. If I read all comments correctly, there is no electrical limitation that explains such ...
by Alan B
Oct 29 2019 2:09am
Forum: E-Bike General Discussion
Topic: Does torque normally change with battery voltage?
Replies: 30
Views: 2488

Re: Does torque normally change with battery voltage?

At very low speeds battery voltage is not much of a problem because back EMF is very low so full torque can be generated. As speed rises the ability to generate the same torque falls off due to back EMF.

What they told you isn't wrong, it is just part of the whole picture.
by Alan B
Oct 29 2019 2:06am
Forum: E-Bike General Discussion
Topic: Does torque normally change with battery voltage?
Replies: 30
Views: 2488

Re: Does torque normally change with battery voltage?

This thread started with an observation about reduced torque due to battery sag. Clearly that is an example of this. There are many ways to think about these electromechanical systems. Some of them lend themselves to understanding more than others. The back EMF of the motor fights the battery voltag...
by Alan B
Oct 28 2019 11:04pm
Forum: E-Bike General Discussion
Topic: Does torque normally change with battery voltage?
Replies: 30
Views: 2488

Re: Does torque normally change with battery voltage?

Lots of good info here, but the motors are the same (as was mentioned). So referring to one as a 36V motor and the other as a 72V motor is confusing. Might be better to edit it and call it the 36V system vs the 72V system. And you can get more performance out of the same motor with a 72V system... T...
by Alan B
Oct 28 2019 7:50pm
Forum: E-Bike General Discussion
Topic: Does torque normally change with battery voltage?
Replies: 30
Views: 2488

Re: Does torque normally change with battery voltage?

The simplest solution is to avoid using the end of the battery capacity where sag becomes a factor. Increase the capacity of the battery by paralleling additional cells. They can be tied in so the BMS, charging, etc remains the same.
by Alan B
Oct 28 2019 7:33pm
Forum: E-Bike Technical
Topic: 60 volt vs 72 volt
Replies: 84
Views: 8957

Re: 60 volt vs 72 volt

I checked, he plans to use them so that didn't help. I may have some other 6S that I should dispose of, not sure. They may not be a good fit for you, 25V full charge works for 25/50/75/100V but skips over some other desirable voltages. I also have a 14S balancing charger that I haven't used in awhil...
by Alan B
Oct 28 2019 4:37pm
Forum: E-Bike Technical
Topic: 60 volt vs 72 volt
Replies: 84
Views: 8957

Re: 60 volt vs 72 volt

Great.

I gave some lipos to a friend, he isn't using them, perhaps I should see if he still wants them. Mostly 6S5AH Turnigy. What are you looking at using?