i have noticed another bug if the shunt mV reading is over 30mV it displays wrong data
i have a shunt 200A 60mV and on 30mV i have exactly 100A if i go over 30mV and 100A it display sometimes 60A or less total wrong numbers and over 30mV the reading in the shunt pcb is inacurate
so to solve this problem i ordered a 500A 50mV shunt because i need 300A so 30mV would be enough
@stuart
NOW THE GOOD NEWS
it is working with my sunny island 8.0h-13 THIS IS AWESOME
but cant be mixed with victron dvcc because the charge voltage need to be 1v higher its a sunny island thing
if i set 57V the charge voltage in sunny island is 56V but 57V on Victron
Any chance you can share your sketch? I am trying to use the KG-F to test and record the voltage and current on a small cell test station I am using to test cells for an EV conversion…
EDIT:I Saw now that you attached it above… Thank you!
So…I got it partially working but I am getting a lot of Bad Checksum messages. Also, when I plug the serial interface in, the screen doesn’t work (it freezes)…
Any ideas? The app is still updating so I know the device is running…
I’m selling off my DIY BMS stuff.
While I totally like this project, I just am not able to finish my build.
4x JKong BMS are now doing my batteries for over 1.5 years, its time to abandon this project for me.
I used to have a setup prepared for 80 cells…, 5 x 16 280AH Eve cells.
Life happened, now 3 x prebuild BYD 260Ah each and one DIY 280 Eve.
Running stable for a long long time…
Never change a winning team:-)
Anyways…
My hoarding collection is roughly this:
33 x 4.0 boards, the heatsink you see is with thermal tape 4.0 boards
I have 25x attiny, 20 to be used for the not yet populated boards.
Possibly Ebay is a better place to sell.
Attiny goes for € 10 there (UK) ( € 2.50 poland)
That is not where the enthusiasts are
This community has given me a lot, I like to give back.
I’m not giving away for free… absolutely not.
You also don’t have to expect to pay 10 bucks for attiny
Just send me a message via OEM forum if you are interested to buy.
I asked Stuard for price indication to sell.
He advised 4 pounds + price of Attiny
4.0 Cell module finished is $7.00 (33 available)
4.40 Cell module to solder is $7.50 (20 available)
4.40 Cell module finished is $8.00 (30 available)
While the cheapest attiny841 available I can find is $2.50, and regular price up to $10…
I didn’t invest to make profits.
I’m asking absolutely fair price.
Stuart advice 40 pounds for the new controller boards
The controller board is $45. All parts included
I have 2 x 2.8inch SPI Module, each $7.50. (when buying controller board)
I have 5 x older controller board, need to be soldered. (all parts included)
they include 4x relay boards, not the wifi modules.
Price $7.50 each
Slow transport is cheap but can easily take up to 6 weeks from Thailand.
FedEx (or other) is $40.
I charge half of it $20.
That is, if the order is above $100
Whole shebang:
83 cell modules, 5x new, 5 x older controller, 2x SPI, 5 extra Attiny841
incl globally transport = $750,-
When people have the urge to read all 4700 posts, they will come across my learning curve with soldering…
I have 27 (!!) 4.0 boards that need rework.
as far as I can say all 27 attiny841 are functional and working.
I had some troubles with the JST, and tried manually solder the thermistor inside the resistor part…
that is way too crazy tiny to do by hand!!
really… I spend hours and hours and hours
(that was before I learned about 177c solder paste, and bake it in an oven ad 180c)
So much simpler!!
Back then, better for me to just order some new boards and new parts (yes, JLC had the thermistor back in stock) then to spend more hours to do rework, as I’m beginner at that part.
Anyways…
27x 4.0 cell modules, need rework.
27 x attiny841, in great demand due chip shortage.
Also available, 5 X older controller boards, with 5x relay.
Just 1 WiFi thingy.
Price $7.50 each.
Transport
10-20 days $10
8-15 day $ 15
3-7 day $ 32.50…
Regular mail with relay $7.50, takes 40 to 60 days (not tracked)
Regular mail without relay $5.00
Regular mail is price per.
As weight goes up fast, it’s quickly an (envelope) parcel, where the price starts at $10
Bigger (thicker) starts at $20, like 250 grams…
More units is more weight, possible little more expensive.
I’m not a business.
I don’t have all the numbers and rates.
This is indicative from what I can find using transport broker, to reduce the costs.
