DIYBMS v4

TroyDangerfield · 2021-01-24T03:04:33.286Z

I am interested, I am in Australia, maybe we could do some kind of bulk build for each country?

stuart · 2021-01-24T08:19:47.266Z

Yes you can mix and match, any idea what killed the other one?

Daemon256 · 2021-01-24T09:14:35.856Z

I am using one 4568 and it connects inverters. At the moment of connection, the capacitors in the inverters are discharged and we practically get a short circuit at this moment. The transistor can withstand. In the next version I will use a thermistor in tandem with it.

Chapulino · 2021-01-24T12:22:14.517Z

Today I have tried to update some module and at the end of the firmware load,If I choose Y the blue led keeps flashing very fast and does nothing else. I get this

if I choose to answer all the questions that No

In the end, if it tells me that the Fuses match your indications but the module, I connect it to a battery and the control does not recognize it, not even any led lights up at the time of the battery connection (the usual thing would be that some of them would flash and then every few seconds a short blink of the blue led)

Thanks

Solved by reprogramming with the USBASP at 5V instead of 3.2V

hotear · 2021-01-24T14:58:53.540Z

It was odd. For over a month I had been seeing one of my packs as lower than all the others and I thought I had a bad cell in there so I got the pack out and tested it. In fact this pack was higher than the others so there was some kind of issue with the diybms module on that pack. When I put it back together and looked at the monitor page it now showed this pack being higher than the others (as it should have). I think somehow unplugging the module had reset something. I thought I’d just reflash it to be sure it was back to normal so I did. Visual studio flashed it and checked it without issue but then proceeded to do it again, and again. In all it reflashed it about 6 times before it finally stopped. After that I plugged it back in to the chain but it no longer worked. I am no longer able to flash it either. I wonder if it had a bit of a bad solder joint somewhere that caused the bad cell voltage reading in the first place and then caused it to fail altogether but it’s very odd. Luckily I also have an Ebike BMS on my packs too in order to provide over charge and over discharge protection so that would have prevented the module being over charged.

stuart · 2021-01-26T17:06:44.461Z

2 posts were split to a new topic: DIYBMS interface to mySQL

stuart · 2021-01-26T17:06:09.366Z

2 posts were split to a new topic: Pre-charge relay when using a main contactor

Tricky · 2021-01-26T18:08:20.800Z

Thank you very much, that sounds like the perfect tool, just finished work, will check it out after i’ve had a bath.

Jon_Coop · 2021-01-26T18:54:59.469Z

Curious what you guys are using as a battery disconnect, controlled by a relay? Solenoids, contactor, mosfet, etc…

In the process of building a PCB that uses 10 - 400a power mosfets in parallel, to connect / disconnect the battery from charger & load.

Basically the exact same circuit I Used to make my spot welder but using slightly different mosfets

stuart · 2021-01-26T19:10:21.980Z

Isn’t the problem with MOSFET that they can get stuck on/fail on?

Jon_Coop · 2021-01-26T20:03:19.836Z

That the same problem with most things… part of the reason why I’m running 10 mosfets in parallel that are rated at 400 amps each. My maximum load should only be 200a - 300a at most. Those 10 mosfets should be theoretically able to carry 4000a… so they shouldn’t fail with 300a… I’m also planning on running a 400a in-line fuse.

But again that’s why I’m curious what other people are using. I’m designing the pcbs anyway for my spot welder to make it look more professional so I figured I would just use the same PCB for my battery disconnect. And obviously I don’t plan on running 300 amps through the PCB traces LOL basically it’ll look like the kweld with big beefy copper rails for the current to flow through

I’ve Been an electrician for 25+ years, and I can’t even begin to tell you how many contactors and solenoids I’ve seen fail. Not necessarily failed closed, just failed in general… and when you’re talkin about 400 amp contactors or solenoids of decent quality, they’re not cheap

atanisoft · 2021-01-26T20:37:23.577Z

Isn’t this what a shunt trip typically would do?

garethb · 2021-01-26T22:50:27.718Z

This is what I’m using. Can hook this up to the relay attached to your bms. Still being shipped so haven’t tested but don’t see why it wouldn’t work… @daromer pointed me in this direction. I think he has one setup.

daromer · 2021-01-27T00:03:10.834Z

Yeap i have. Several actually …above is My video so

garethb · 2021-01-27T00:15:30.556Z

haha, didn’t even pick up on that

rosetta85 · 2021-01-27T03:18:01.814Z

Count me in on a group buy but I’m in the States…

beindi · 2021-01-27T11:43:05.376Z

I had the forum translated into Spanish. She had to have written it in English. Apologies

garethb · 2021-01-27T23:46:46.367Z

I’d be in for a group buy in Australia

stuart · 2021-01-29T08:46:59.414Z

2 posts were split to a new topic: Modules for sale on www.batterysecondlife.com

gazzaman2k · 2021-01-28T18:38:28.078Z

ive been using georges leaf bms on my nissan leaf cells since about the 2nd week he released them they have been rock solid and work perfectly fine and that about 8 months now