Search found 320 matches

by BShady
Nov 28 2017 9:31am
Forum: Battery Technology
Topic: DC to DC Boost converter for lipo charging
Replies: 5
Views: 963

Re: DC to DC Boost converter for lipo charging

do DC-DC converters output Watts need to equal the input Watts?
I was thinking of doing this too but using the Boost converter to power a 10s BMS.
by BShady
Nov 26 2017 1:38pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

i thought of that but i soldered another wire on to both ends and it still worked. sorry the last image didnt load properly. its the white loop wire that im talking about
by BShady
Nov 25 2017 6:06pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

i just soldered another separate wire to each of those ends and now it works!?

IMG_20171125_174631-1296x2304.jpg
by BShady
Nov 24 2017 3:14pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

The madness doesn't stop!!!! So i took the last 2 remaining mosfets that worked on the breadboard and soldered them to the circuit. I turned on the circuit and everything turned on but the output voltage was only at 30v. I checked the gate voltage and it was only 2.5v. Weird. So I de-soldered the ci...
by BShady
Nov 22 2017 9:53am
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

I think i spoke too soon I just tried putting the "bad" mosfets on a breadboard and testing them like that (instead of soldering them in circuit) and they worked fine!? I put a nice size heat-sink on them as they where getting pretty hot. IMG_20171122_093803-1036x1842.jpg the orange wires were conne...
by BShady
Nov 20 2017 6:50pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

There are lots of counterfeit parts in the low cost channels. Beware. Driving PWM into FETs requires more drive, and FETs in parallel may not share current very well. It helps to match them, but in any case you cannot assume the rating doubles with the second FET. There are guidelines for this, as ...
by BShady
Nov 20 2017 6:00pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

Problem solved!!!!! Fechter you where right! fets where a garbage! lesson learned don't buy from ebay or amazon! I tried this fets with no load and they never failed!!! FDP18N50 http://www.mouser.com/ds/2/149/FDPF18N50T-1008232.pdf im not going to use these for my switch but they where a good test!...
by BShady
Nov 20 2017 5:31pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

They are isolated. Will try some different FETS and let you know
by BShady
Nov 20 2017 3:41pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

I did add one thing to the circuit but it doesn't seem to be to be what would cause the issue: I used a DPDT switch and to the second pole i connected a high voltage buck converter to power my receiver. The converter is connected straight to the negative input and the positive is connected by the sw...
by BShady
Nov 20 2017 9:27am
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

i am using the one with the switch. this is all happening with the pack voltage at 46V. .i checked the zener diode. the second i connect my probes i see 18V on the multi-meter and then it quickly shoots down to 11.5 this while the zener is still in circuit with the rest of the components. however as...
by BShady
Nov 20 2017 12:46am
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

Im using active PRE-Charge 3B

FETS: irf3205
Pack Voltage: 12s Lipo
by BShady
Nov 20 2017 12:12am
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 733
Views: 91244

Re: Active pre-charge/inrush control

hey i have been using the Active pre-charge circuit 3b for some time now and recently noticed that all this time 1 of my 2-FETs in parallel was blown. problem is every time I solder another in parallel the one that didn't blow last time blows!! i even put 4 (fresh ones) in parallel and they all blew...
by BShady
Sep 23 2017 7:45pm
Forum: Battery Technology
Topic: 2 Wire BMS
Replies: 6
Views: 808

Re: 2 Wire BMS

Billvon

i understand how the BMS works but i was asking (amberwolf answered) if the charger will damage the ESC as it is also sending voltage to the ESC directly on a 2 wire BMS. My problem was answered by amberwolf.
by BShady
Sep 19 2017 6:23pm
Forum: Battery Technology
Topic: 2 Wire BMS
Replies: 6
Views: 808

Re: 2 Wire BMS

of course!! you need a load!!

Amberwolf thank you.
by BShady
Sep 15 2017 4:58pm
Forum: Battery Technology
Topic: 2 Wire BMS
Replies: 6
Views: 808

Re: 2 Wire BMS

billvon wrote:
BShady wrote:For the 2 wire BMS's the load and charging are connected to the same terminal. does that mean i have to disconnect the ESC from the BMS every time i want to Charge the Batteries?
No, it handles that just fine.
can you explain how it does that?
by BShady
Sep 15 2017 4:47pm
Forum: Battery Technology
Topic: 2 Wire BMS
Replies: 6
Views: 808

2 Wire BMS

Hello I was looking into getting a BMS for my 12s Battery pack but i saw there is 2 wire and three wire BMS's. i already read up on other posts about the differnece with pros and cons. I had only one qu. For the 2 wire BMS's the load and charging are connected to the same terminal. does that mean i ...
by BShady
Sep 06 2017 12:21am
Forum: E-Bike General Discussion
Topic: Two Wire BMS
Replies: 12
Views: 4891

Re: Two Wire BMS

3 wire BMS is what is generally used for most ebike packs, in my experience. I'm not sure why, but when a BMS is configured as 2-wire, it can't deliver the same current levels, from the same number/type of fets (at least that is the case for the BMS maker we use). This means an equivalent rated 2-w...
by BShady
Sep 04 2017 11:32pm
Forum: Battery Technology
Topic: How does a BMS work
Replies: 15
Views: 2262

Re: How does a BMS work

Just get a 50.4v cc-cv charger 3a. It will shut off when full. I have a 12s BMS. All I need is something to power it. I have a ton of old computer power supplies capable of out putting 12v 20A. Therefore I would rather spend $6 on a boost converter and use the old power supplies then spend $25 and ...
by BShady
Sep 03 2017 6:20pm
Forum: Battery Technology
Topic: How does a BMS work
Replies: 15
Views: 2262

Re: How does a BMS work

So if I charge the lipos thru a BMS with a 12v computer power supply boosted to 50.4v with a boost converter I should be fine?

On the boost converter I can limit the max current. So I can limit it to 3 amps for my 5Ah lipo, which is .6C.
by BShady
Aug 30 2017 9:27pm
Forum: Stand-up E-scooters and E-skateboards
Topic: Meepo Board
Replies: 4
Views: 2268

Re: Meepo Board

The kid just sent me this link. Some guy reviews boards and made a blog on it. http://www.electricskateboardhq.com/kierans-meepo-the-person-the-board-the-story/ He said one thing that pissed me off! Check the ESC section of his review and tell me if you catch his mistake as well! Hint he compares it...
by BShady
Aug 30 2017 9:09pm
Forum: Stand-up E-scooters and E-skateboards
Topic: Meepo Board
Replies: 4
Views: 2268

Meepo Board

Hello friends. I haven't been here in a long while. I have build 2 electric boards when buying a premade one costed way to much and weren't half as good! All thanks to this community for all the help I got. What has brought me back is I started to inspire younger kids to start to build their own boa...
by BShady
Oct 28 2016 9:43am
Forum: Battery Technology
Topic: How does a BMS work
Replies: 15
Views: 2262

Re: How does a BMS work

can i just use a boost converter from 12v to 50.4? i already have a 12v charger and the boost converter cost like 5 bucks.

btw just to make sure im right i need to supply 50.4v to the bms?
by BShady
Oct 26 2016 8:44am
Forum: Battery Technology
Topic: How does a BMS work
Replies: 15
Views: 2262

Re: How does a BMS work

what power supply supply would you use for a 12s li-ion BMS?
by BShady
Sep 09 2016 2:27pm
Forum: Battery Technology
Topic: SAVE THE LIPOS!!
Replies: 8
Views: 978

Re: SAVE THE LIPOS!!

You guys are not going to believe this! so i already read amberwolfs thread on lipos on how they could be dangerous. I wont lie, you guys got me a little more nervous about keeping this cell and lipos in general. i was already carefully never over charged or over discharged and never left the batter...
by BShady
Sep 09 2016 1:25pm
Forum: Battery Technology
Topic: SAVE THE LIPOS!!
Replies: 8
Views: 978

Re: SAVE THE LIPOS!!

HAHA! i didnt think it was that bad!! i have put these batteries thru hell, no joke!! :twisted: Shorted out the batteries (all the packs) at least 6 times! :shock: one time it totally chewed up the plastic protection part and the metal, didn't change the connector and im still using it today! 8) ill...