Search found 4546 matches

by izeman
Feb 21, 2018 4:22 am
Forum: General Discussion
Topic: Forum software upgrade on 11/17/2017 technical issues thread
Replies: 135
Views: 7766

Re: Forum software upgrade on 11/17/2017 technical issues thread

Is there a plan to add tapatalk support again?
by izeman
Feb 20, 2018 4:06 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

i measured current flow at cell#15 in stanby and with active BT connection. w/o BT connection it's hardly measureable. 1mA blinking every now and then, and then showing 0mA again. when active i see 13mA. the question now is: how ACCURATE is my fluke at such low current flows? but still it proves the...
by izeman
Feb 20, 2018 11:01 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

to make things clearer to follow it may make sense to post a picture of the BMS everyone is talking about so it's clear. MY BMS has seperate charge and discharge FET-banks, and they don't share a common dis/charge port. it also has the K1 connector, which others don't seem to have. so a picture is m...
by izeman
Feb 19, 2018 6:11 pm
Forum: Battery Technology
Topic: my 18650 frame pack build
Replies: 22
Views: 749

Re: my 18650 frame pack build

Very nice work and it fits in the battery box when you're done that's always a worry to you get it to fit. Good job thanks! yes, it was a great moment when i let the battery slip in for the first time :) unfortunately the battery is maybe a millimeter to wide. so i had to add some rubber seal to th...
by izeman
Feb 19, 2018 6:09 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

@electricgod: .) my phone is brand new. it's a xiaomi mi mix2. with the original firmware it was working fine. rooted it, installed a beta rom from xiaomi to get oreo, and it failed to connect. well, at least i know how to make it work again -> downgrade. .) it wouldn't suprise me to see a voltage d...
by izeman
Feb 19, 2018 6:03 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

I wouldn't pay too much heed to the individual cell voltages unless you've calibrated all cells using a Fluke or other high quality multimeter, same goes for the charging currrent. i thought i would need to calibrate them as well, but tested with my fluke meter and they all were within 1mV. so no n...
by izeman
Feb 19, 2018 3:06 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

I suppose you could put the amp meter on the batt- balance wire. Why would the regulator circuit be connected to anything less than batt- and batt+? Everything else would be bad since it would drain lower cells faster than upper cells. at least i could test the most negative, most positive balance ...
by izeman
Feb 19, 2018 2:54 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

That's a fair point, in the video I posted he is measuring the current on cell 14 only. I will measure mine with only ground and cell 7 connected and report back, unfortunately it will be a few days before I can report back. that's the problem, as the BMS is powered by all balance wires it's next t...
by izeman
Feb 19, 2018 2:52 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

ElectricGod wrote:
Feb 19, 2018 1:52 pm
The latest software can be found here.
https://www.lithiumbatterypcb.com/smart ... -download/
thank you, unfortunately this version doesn't work either for me. :( i had one minor version earlier 2.1.1010)
by izeman
Feb 19, 2018 2:50 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

Where is this K1? I have the 16-20S BMS and I don't see it anywhere. Can you post some pic's please? please check my posts from the last days. there's a picture. i don't want to double post for readability. the K1 connector which is not populated is directly next to the two temperature probe connec...
by izeman
Feb 19, 2018 2:46 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

I think the electronics are powered by the entire pack voltage and you said that can't be the case. I think those 6 transistors and some other components make up a linear regulator that runs at pack voltage, but I'm not 100% sure...yet. A regulator would operate at a wide range of input voltages an...
by izeman
Feb 19, 2018 1:32 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

which assumptions are wrong? i don't see you say anything different than i do. my BMS is 15s so around 50-60V. and something has to power the 12V for the BT module, and i guess the atmel is always on as well (i should be in sleep mode though). i will need to measure that. still i see some voltage dr...
by izeman
Feb 19, 2018 7:52 am
Forum: Battery Technology
Topic: my 18650 frame pack build
Replies: 22
Views: 749

Re: my 18650 frame pack build

finished the packs over the weekend, and i'm really happy with the outcome. i made some small caps to guide the balance wires. there are no sharp dents and the wires won't be bent to much. the caps were designed with fusion360 and glued to the battery with the glue gun. IMG_20180216_082329.jpg then ...
by izeman
Feb 19, 2018 7:27 am
Forum: General Discussion
Topic: Perth bike path speed bump trial set to force speeding cyclists to slow down
Replies: 9
Views: 116

Perth bike path speed bump trial set to force speeding cyclists to slow down

http://www.abc.net.au/news/2018-02-19/s ... th/9460750

how lucky are we, that we live in a world that has no worse problems than speed bumps for bikes ... :roll:
by izeman
Feb 19, 2018 7:21 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

anyone got any information about STANDBY drain? i realized that the 12v rail for the BT module is "always on". so the processor and other stuff is "on" as well. i read that standby current should be around 0.2mA w/o BT connected. but at what voltage? voltage of the pack? can't be. those BMS range fr...
by izeman
Feb 19, 2018 5:19 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

Also, can someone upload a recent version of the android app and pc program please? i'm not sure it's the app's version, but maybe the bluetooth stack used on oreo maybe? i even can't SEE the bms! also tried different BT scanner apps, but they can't see it, whereas my "old" android has no problems ...
by izeman
Feb 18, 2018 4:43 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

well, half the internal resistance produced only a fourth of heat. so this will be a plus.
i don't see why the BMS is rated so conservatively. even with 10x junk FETs it should be able to do WAY more than 50A.
by izeman
Feb 18, 2018 12:49 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

YES!!! i works! :) just connect a latching switch to K1, enable SWITCH in eeprom (windows software) and voilá! you can switch the BMS on/off with it. if you DISABLE the SWITCH checkmark in the software it will be ALWAYS ON. edit: it's a bit strange: i can easily connect with my redmi note 3 android,...
by izeman
Feb 18, 2018 11:48 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

flippy wrote:
Feb 18, 2018 11:34 am
i am looking for a mosfet that can do more then 75v. my next battery is ~115v charged.
and takers for a solid mosfet choice for these voltages?
first to mind would be IRFB4115 capable of 150V, but resistance is very high (~10mOhm)
by izeman
Feb 18, 2018 8:09 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

The mosfets are HY3410's which are really low grade...100 mOhm, 17 amp...meh. I'll be replacing them with something better. Mine got irfb 3607. Even if they are genuine (what i doubt) those have an internal resistance of 7-9mOhm which is quite high. Replacing them with some 3077 will help a lot and...
by izeman
Feb 18, 2018 6:41 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

Inwo wrote:
Feb 18, 2018 4:58 am
Was using that as an example.
Disconnecting B+ or another lead should turn off mosfets.
no. battery positive i not even connected to the BMS. the BMS takes it's power from the balance wires (which of course ARE connected to B+).
by izeman
Feb 17, 2018 6:36 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

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?
by izeman
Feb 15, 2018 12:11 pm
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

plateau wrote:
Feb 15, 2018 10:43 am
Could you check if these pins have a pull-up resistor? If so, it could be to use a push button to switch between the charge and discharge.
how would i do that?
one pin is connected to GND, the other measures 1mOhm against ground (raising the longer you measure)
by izeman
Feb 14, 2018 3:41 am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 172
Views: 6555

Re: bluetooth BMS?

i opened my bms yesterday. first of all to install a parallel 16pin jst-xh connector so i can connect 2 paralleled packs. please ignore the small B- wire, it was for testing only. it is needed to get valid readings of cell voltage. if it's not connected the cells 1-3 show wrong values. i still want ...
by izeman
Feb 12, 2018 10:25 am
Forum: Battery Technology
Topic: my 18650 frame pack build
Replies: 22
Views: 749

Re: my 18650 frame pack build

printed endcaps last night, they guide the wires and protect the ends of the battery 2018-02-12 at 07.41.32.JPG added some extra protection tape. you can never have enough protection, right? ;) 2018-02-12 at 07.57.24.JPG lots of silicone to glue the caps to the battery. they stick nicely, even with ...