Search found 1524 matches

by ElectricGod
Feb 17, 2018 3:22 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 89
Views: 5972

Re: bluetooth BMS?

i don't have those copper bars on my BMS. should i add them? electricgod: did you find a way to add an on/off switch? i'd like to get rid of my inrush limiter (one component less to fail) and use the BMS instead. any ideas? I'd add copper to the power traces. Some 14 or 16 awg wire ought to do it. ...
by ElectricGod
Feb 17, 2018 6:16 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 89
Views: 5972

Re: bluetooth BMS?

Thought I'd add a little about these BMS. The android app works pretty well see below for screen shots. But first screen shots of the BMS. I bought 2 of these BMS and both have this nice chunk of copper reinforcing, but they don't do much good since they are in the wrong place and don't reinforce th...
by ElectricGod
Feb 12, 2018 12:06 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 69
Views: 1907

Re: R Martin EVD Moped with HubMonster

I hope your luck doesn't run out. I'm glad I learned the lesson with nothing more than losing one pack and having to clean soot off of a table. Plenty of others haven't been so lucky, and it's quite likely we've lost at least one forum member to lipo and never known about it. I've heard the LIPO FU...
by ElectricGod
Feb 12, 2018 4:28 am
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 69
Views: 1907

Re: R Martin EVD Moped with HubMonster

Yes, the little 4s RC lipo pack was just sitting there for at least a month on a table with each pack spaced apart about 5" after I checked a new shipment of 20 packs for balance. It was in our fan ventilated guest house that no one but me entered, so I know for a fact that they were undisturbed. I...
by ElectricGod
Feb 12, 2018 4:09 am
Forum: E-Scooter and Motorcycle General Discussion
Topic: E-Bike XB502 conversion project
Replies: 156
Views: 13892

Re: E-Bike XB502 conversion project

I've been busy with LED's and chargers and batteries. I also got the Pantera moped running and sold it off for $400. I had a bunch of SLA's and an old controller that went in it to get it running. Cost me nothing but an hour to get it running again. Anyway, it's been a while since I made any progres...
by ElectricGod
Feb 11, 2018 5:57 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 69
Views: 1907

Re: R Martin EVD Moped with HubMonster

I can get LTO's in the USA for $8.33 per 11Ah cell. Probably a bit cheaper if I bought lots more at the same time. Since there's no need for a BMS, this makes for a cheap power storage source. I've read stories of them getting damaged, smashed and punctured and nothing happens. I've never had an iss...
by ElectricGod
Feb 09, 2018 11:36 pm
Forum: Battery Technology
Topic: My excellent adventure through some battery builds
Replies: 119
Views: 15528

RMartin EVD battery builds

I've been putting together batteries for the RMartin. I had ten 10,000 mah LIPO packs which is 2 short of making a 3 16S packs so I bought a couple more to make this 30Ah pack. There's 3 banks of 16S and they each get their own BMS. I had 2 identical 16S BMS and one from another source. I've bought ...
by ElectricGod
Feb 09, 2018 11:30 pm
Forum: Battery Technology
Topic: My excellent adventure through some battery builds
Replies: 119
Views: 15528

INR21700-48G testing

My final conclusion is that the INR21700-48G cell is not very compelling.

The best I saw was 4400mah and more often 4200mah. That's soooooo not 4800mah! Disappointing is what I call that!
by ElectricGod
Feb 09, 2018 11:24 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 69
Views: 1907

Re: R Martin EVD Moped with HubMonster

I've been putting together batteries for the RMartin. I had all of these 10,000 mah LIPO packs except for 2 so I bought a couple more to make this 30Ah pack. There's 3 banks of 16S so they each get their own BMS. I had 2 identical 16S BMS and one from another source. I've bought another 16S BMS for ...
by ElectricGod
Feb 09, 2018 7:29 pm
Forum: E-Bike Photos & Video
Topic: A2b metro gti
Replies: 77
Views: 5262

Re: A2b metro gti

PM is noit working for you and your post in my multitooth motor thread disappeared.
by ElectricGod
Feb 07, 2018 3:06 pm
Forum: Battery Technology
Topic: Samsung INR21700-48G
Replies: 31
Views: 2860

Re: Samsung INR21700-48G

Well I am done testing INR21700-48G cells! The INR21700-48G is disappointing. The best I have gotten is 4400mah and typical has been 4200mah. I've never gotten 4800mah and IR is pretty high. I seriously doubt I will buy more of this cell. I've now charged and discharged every one of the 40 cells I h...
by ElectricGod
Feb 07, 2018 2:42 pm
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

The best balance for conventional affordable silicon stator lamination material is +-1.5T field flips 700-1kHz commutation freq (this is unrelated to PWM freq it uses for current control during the commutation pulse). 50/50 Cobalt/Iron laminations can flip about +-2T up to 1.3kHz commutation freq, ...
by ElectricGod
Feb 06, 2018 4:35 pm
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

If you wanted to improve motor torque per unit of motor weight, you would do the opposite and double the number of teeth and double the number of magnets. Then that also doubles the amount of switching fields back and forth and doesn't that increase iron losses? I understood that less stator teeth ...
by ElectricGod
Feb 05, 2018 7:52 pm
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

If you wanted to improve motor torque per unit of motor weight, you would do the opposite and double the number of teeth and double the number of magnets. Then that also doubles the amount of switching fields back and forth and doesn't that increase iron losses? I understood that less stator teeth ...
by ElectricGod
Feb 05, 2018 6:33 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 69
Views: 1907

Re: R Martin EVD Moped with HubMonster

Voltron wrote:
Feb 05, 2018 6:00 pm
Craigslist is great for that...

scoots.JPG
where are those located? How much?
by ElectricGod
Feb 05, 2018 1:37 pm
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

A high-tooth-count wide stator (with deep/large slots for lots of copper if you need that) could probably make more active copper vs end copper? Keep in mind hte magnets on the end probably won't end up as separate domains; they'll either integrate or interfere with the other magnets. Plus, they'd ...
by ElectricGod
Feb 05, 2018 2:29 am
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

IIUC, (simplification follows) since they're not parallel with the magnets (i.e., parallel with the slots), you can't, really--the force created from that non-parallel flow in them doesn't act on the magnets the way the force from the parallel ones (in the slots) does. If there was any way to only ...
by ElectricGod
Feb 04, 2018 7:33 pm
Forum: Items for Sale - New
Topic: KMX Trike Frame kits for cheap!!!
Replies: 21
Views: 978

Re: KMX Trike Frame kits for cheap!!!

Trike frames are still available
by ElectricGod
Feb 04, 2018 2:57 pm
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

Major...

Is that why side by side teeth are always wound forward/reverse/forward so that you don't waste copper?

How about those end turns? How can we take advantage of them?
by ElectricGod
Feb 04, 2018 12:31 am
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

My thought is to reduce iron losses. Typical hub motors have so many teeth and switching as a result is quite high. Same for large outrunners. This increases iron losses significantly. Winding teeth side by side the same direction AND also using larger magnets that span that same number of teeth wil...
by ElectricGod
Feb 04, 2018 12:19 am
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 69
Views: 1907

Re: R Martin EVD Moped with HubMonster

I've been hunting for another of these motors or moped. I did find a motor a couple of weeks ago, but it had already been sold. If I want to drive 1800 miles, I found another R Martin. I was hoping for something a bit closer. Maybe I can get the seller to crate up the bike and ship it to me. If you...
by ElectricGod
Feb 03, 2018 7:54 pm
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

I'm struggling to understand what you propose (a simple diagram would have been very useful) but it sounds like you want to wrap a winding around several adjacent teeth, bridging the gaps between the teeth. My initial impression would be that this would most likely screw up the magnetics somewhat a...
by ElectricGod
Feb 02, 2018 10:19 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 69
Views: 1907

Re: R Martin EVD Moped with HubMonster

You diving down a rabbit hole. When you divide the slot and pole count by half (everything else the same), it will significantly increase Kv, maybe by more than 2x (I haven't chased that rabbit far enough to say exactly). For someone who can do their own controllers there's no benefit to going 6 ph...
by ElectricGod
Feb 02, 2018 9:29 pm
Forum: Motor Technology
Topic: Multitooth motor winding idea
Replies: 27
Views: 558

Re: Multitooth motor winding idea

I have this idea... All you really smart folks out there this is your big chance to blind us with your intellect. Please feel free to point out the flaws in my logic or where I flat out missed things, made mistakes or you know something I don't. That's the whole idea. 1. Make a 26, 32 or 52 tooth s...
by ElectricGod
Feb 02, 2018 7:49 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 69
Views: 1907

Re: R Martin EVD Moped with HubMonster

Most brushless motors will have a stator tooth count that is a multiple of 3. Magnet count is always a multiple of 2. If using overlapping windings, each winding counts as one tooth, even if there are 3 teeth inside the winding. The iron losses are largely from hysteresis and eddy currents, so by r...