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ENJ Power for Heltec/JK BMS

That's why I wish it was open source. I could add support for it. That said, I'm happy using Grafana to do all the monitoring - it's much more flexible anyway.
I'm not using SA (actually I'm just not smart enough to set it up, I'm a Microsoft guy so when i started this a couple years ago, even a bash script was alien language to me, let alone python), so i wrote my own .netcore code that sucks up BLE data from the JK's and PI17 over hidraw (USB) from my inverters to a local influxdb on my tiny SBC which is then displayed in grafana, which i put behind a CloudFlare tunnel so i can access it from anywhere safely without a vpn. I don't think I'll want to learn python any time soon, brain's already full. But i might put all of this into an Arduino sketcher (ESP32?) project and turn it into a REST library and make that open source so others can code in their fav tongue .. that's one of those "I'll eventually get around to it" kind of projects along with my race car and flying boat builds.

@daniel32768 the BMS can theoretically handle more. I've seen it surge to over 360A without frying itself. Over temp protection does kick in at 90°c and doesn't release until below 75°c. It was drawing ridiculous power due to a price surge (in my favour) where grid export prices hit over $10/kWh. My code kicked in and sold the maximum amount of electricity it could (at the time i only had 2x inverters out of 3 on the grid so it was selling @ 20kW... My bot made me over $100 in half an hour. That kind of spikes don't happen very often here though, maybe only twice a day and 5 days a week for a few months a year here, but when it does, the spikes alone pays for my whole system in a year.

Incidentally I'm planning to double the size of my system yet again, didn't someone here say they got direct contacts to the mfg/dist for the JK BMS's? I'm about to order a few more lol..
 
@lonertic so the code is C# ? That is music to my ears since i started coding about 3 years ago and my sauce of choice was C# (mostly WinForms because i needed a way to quickly develop windows GUI apps). Then i discovered i am able to use it for linux to have some backend work done.
Would you be so kind to share your code/setup for extracting/graphing data off the BMS ?
Regarding the modding of the BMS i think i'll give up ... too high chance of ruining it and the cable i got is bad (insulation is deteriorating upon applying temperature).
So i'll be getting a second bank of 16 x 280Ah EVE cells + the second JK bms.
This way load per bank/bms will not exceed 5-6KW (100-120A).
I don't like things running hot to the touch.
My setup/inverter is off-grid i did not want to fiddle around for the on-grid paperwork and stuff.
 
Hello everyone ! This is my 1st post on DIY Solar Forum.
I am getting the solar hype (i bet y'all know how it feels like) on my little weekend house (15km away from my apartment - still prefer the apartment - house is smaller in interior space).
I got 4KW worth of solar panels, PIP 11KW max inverter (wanted most powerful single phase all-in-one inverter that i could get my hands on), and 16x EVE LF280K LiFePO4 cells (~ 14KW) , ofc accompanied by JK BMS - the almost perfect BMS out there ( JK - B2A24S20P ).
I am completely off the grid as of now (Grid breaker is off - inverter was pulling 35W at night for no reason (priority - SBU) and rest from batt).

And now ofc comes the desire to monitor everything remotely.

I got a RPi 4 connected via USB with the inverter - with SolarAssistant installed on it - very nice for the inverter side of the data.

View attachment 94930

And since JK BMS is not supported yet by them (i am emailing back and forth trying to convince them to implement it - even pointed them to the python BLE library that wirelessly talks to it - we'll see if they finally do it).
For now i got an old android 5 tablet with remote software (AirDroid) and last version of JK-BMS that still works on Android 5 ( 4.2.0 ) and it does the trick ... but only accessible from PC. I connect with anydesk to my PC when i am away - to see the airdroid window connected to the tablet ?.
Fiddly but it works ...
I'd love grabbing the raw data with the other RaspBerry pi (v3) i have laying around and put it in a grafana.
Hey I just got an email from solar assistant:

I apologise for the massive delays. Is it possible for you to:
If that is the case, there will be support for JK BMS by Monday.

Kind regards
Pierre

Unfortunately it's not possible for me to do this ATM as my solar setup is in another country. Maybe you can help them out?
 
Hey I just got an email from solar assistant:



Unfortunately it's not possible for me to do this ATM as my solar setup is in another country. Maybe you can help them out?
Sorry ... i was at my weekend house this weekend (yes, the off-the-grid one where i have my solar setup) and did not check the messages here (i did not research on how to get email notifications either)
Unfortunately i do not have any kind of cable for the JK bms ... i only have the RPi 4 with solar assistant in same room as the JK bms.
I don't even know where to get a cable ASAP for it.
And the inverter connected to the RPi with a regular micro usb.

I think the bluetooth way, altho maybe just 98% reliable might be the best choice.

However, if it must be the cable, i'll find a way.
I am located in Romania.
If you can help with what kind of cable is required , where to get it and/or schematic if it requires fiddling around with the port, i am happy to do it.
Meanwhile i'll be doing some research on my own. I really wanna get this going.

Daniel.
 
Sorry ... i was at my weekend house this weekend (yes, the off-the-grid one where i have my solar setup) and did not check the messages here (i did not research on how to get email notifications either)
Unfortunately i do not have any kind of cable for the JK bms ... i only have the RPi 4 with solar assistant in same room as the JK bms.
I don't even know where to get a cable ASAP for it.
And the inverter connected to the RPi with a regular micro usb.

I think the bluetooth way, altho maybe just 98% reliable might be the best choice.

However, if it must be the cable, i'll find a way.
I am located in Romania.
If you can help with what kind of cable is required , where to get it and/or schematic if it requires fiddling around with the port, i am happy to do it.
Meanwhile i'll be doing some research on my own. I really wanna get this going.

Daniel.
I bought the RS485 cable the BMS here on AliExpress;
US $9.90 | Jikong BMS RS485 CAN module

I have no experience with using the Bluetooth method. Tho I have got it working on grafana using this python code from GitHub.


What I’ve also learned from that GitHub link is that the RS485 cable is not needed. A simple USB to TTL will do.
 
@lonertic so the code is C# ?
Yup c#, originally .net core, now .net5. currently only sending a few fields, like %/Ah remaining, current power (in W's) etc. The raw data is sent to influxDB on localhost (skipping messaging), then HomeAssistant+Grafana on another box does my pretty graphs from the Influx data. Future plans include toggling the BMS or even setting advanced params. The changelog on JK BMS app suggests there'd been a lot of protocol changes in the last 12 months, including encryption!! So now I'm a bit worried that all that data capture I did last year is all moot if the protocol is changed. Hence I'm looking for support from JK original manufacturer to better futureproof this.

... the cable i got is bad (insulation is deteriorating upon applying temperature)....This way load per bank/bms will not exceed 5-6KW (100-120A).
I've been kinda surprised that my 200A JK's have momentarily run up to 300A too. It got very hot very quickly but luckily the power draw slowed down immediately. Agreed, I set my 200A BMS to around 150A constant, I love the fact that it has settings for that!. I run 0 AWG's (70mm2) cables on my batteries. at 150A x 3 battery banks it barely gets warm.

My setup/inverter is off-grid i did not want to fiddle around for the on-grid paperwork and stuff.
WRU? I'm in Aus and i have the opposite problem. there are hundreds or housands of solar companies doing really good deals but none of them will give me an offgrid/hybrid setup cos of how the CEC credits work (colloquially, and incorrectly, called a "rebate" locally). So I'm having a hard time convincing any installers to put in hybrid/offgrid inverters, they all seem to gimme the usual "why u do dat? dat sound stupi, why u like waste money?" etc..sometimes I just wanna reach over the phone and tell them to ST*U and just gimme what i asked lol!
 

You can probably contact them for the CAN side as well. The connector itself is a JST XHP if I remember correctly.
I've got the new version (hardware 8 maybe?), cant remember if HW6 is the same, but this is where it gets interesting. It's a JST GH style socket but the pitch is 1.0mm. I cannot find anyone selling a JST GH 1.0 male socket. There are plenty of JST GH 1.25, but not 1.0mm. and it's also a 3 pin instead of 4 pin as per your github, so, not quite sure what the pinouts are anymore.
 
Good Day Nami
I wanted to Thank You for your helping with the JKBMS' and "hearing" the membership.
It would be great if we could "glue together" into one Thread, all the valuable information you have provided. It is a small Treasure Trove.

I would like to make a suggestion, which I feel only makes sense .
Would it not be possible to just INCLUDE the JST connector(s) with 10cm wire leads with the BMS ?
Or at a minimum include the specifications for the Type & Size of connectors for each port within the description.
In reality, the extra "pennies" for that extra added wires is worth it for Customer Service/Support.

Thanks for your Time & Efforts here
Steve_S
 
This is an embarrassing problem because all the connectors except RS485, which is standard JST1.25, are non-standard plugs and can not be found in the retail market because they are manufactured in batches by professional factories.
Good Day Nami
I wanted to Thank You for your helping with the JKBMS' and "hearing" the membership.
It would be great if we could "glue together" into one Thread, all the valuable information you have provided. It is a small Treasure Trove.

I would like to make a suggestion, which I feel only makes sense .
Would it not be possible to just INCLUDE the JST connector(s) with 10cm wire leads with the BMS ?
Or at a minimum include the specifications for the Type & Size of connectors for each port within the description.
In reality, the extra "pennies" for that extra added wires is worth it for Customer Service/Support.

Thanks for your Time & Efforts here
Steve_S
 
This is an embarrassing problem because all the connectors except RS485, which is standard JST1.25, are non-standard plugs and can not be found in the retail market because they are manufactured in batches by professional factories.
Embarrassing indeed. I had to wait for my supplier to get me the wiring and finally had it air shipped to me.
That further highlights WHY the RS485/CanBus connector with "pigtail" wire leads should be supplied. That is something to get the designers to change on future models.
 
Hmm I must've got a very strange version then? 3 pins on the CAN/RS485 port. measures exactly 3mm apart (so 1mm pitch), and it's a JST GH style socket which is typically only available in 1.25mm pitch.
1654524907824.png

I agree with @Steve_S here - would you guys be able to provide some "pigtails" for these special plugs? For instance, my version has the K+/- line to activate BMS, yet I dont have a display screen (was never sent one, nor told the option I should buy one). If I had a pigtail I can at least create a momentary switch to enable BMS. Without it, I had to find a very small metal tweezer to short pins K+/- without touching any other pins. It's obviously not ideal to work with. So if pigtails are available, I'd like to order some!

----
EDIT: lol like literally 1 second after i posted reply I realised my idiocy!.. 3 pins is 2 pitches apart... so 1.25mm does sound about right cos that could be exactly 2.5mm distance between the 3 pins (call it parallax error since im hovering the verniers above the connector). Confirmed on the 6 pin plug too since that's 6.25mm between the 6 pins (so 5x1.25) ... In that case I'll try some JST 1.25mm connectors and see if that works.
 
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If the customer purchases a BMS configured with CANbus, the CANbus chip will be built-in, and the CANbus function can be used only by using three wires from this interface,
Embarrassing indeed. I had to wait for my supplier to get me the wiring and finally had it air shipped to me.
That further highlights WHY the RS485/CanBus connector with "pigtail" wire leads should be supplied. That is something to get the designers to change on future models.
 
If the customer purchases a BMS configured with CANbus, the CANbus chip will be built-in, and the CANbus function can be used only by using three wires from this interface,
so, without the CANbus chip, are those 3 wires just normal TTL serial signal then?
 
Sorry ... i was at my weekend house this weekend (yes, the off-the-grid one where i have my solar setup) and did not check the messages here (i did not research on how to get email notifications either)
Unfortunately i do not have any kind of cable for the JK bms ... i only have the RPi 4 with solar assistant in same room as the JK bms.
I don't even know where to get a cable ASAP for it.
And the inverter connected to the RPi with a regular micro usb.

I think the bluetooth way, altho maybe just 98% reliable might be the best choice.

However, if it must be the cable, i'll find a way.
I am located in Romania.
If you can help with what kind of cable is required , where to get it and/or schematic if it requires fiddling around with the port, i am happy to do it.
Meanwhile i'll be doing some research on my own. I really wanna get this going.

Daniel.
Support as been added in the new Beta!
unfortunately I won't be able to test it until the 25th.
 
My Seplos 280ah Masons just arrived today finally, so I will be moving my current JK based battery cells into their new Seplos BMS home.

Which means if anyone is interested in two proven but slightly used 200amp 2amp active balance Heltec/JK BMS's, they are available. Make me an offer and I can ship them overnight if needed.
 
My Seplos 280ah Masons just arrived today finally, so I will be moving my current JK based battery cells into their new Seplos BMS home.

Which means if anyone is interested in two proven but slightly used 200amp 2amp active balance Heltec/JK BMS's, they are available. Make me an offer and I can ship them overnight if needed.
@Sanwizard Send me a message if you're in the states. I just may take them.
After looking at my current Jk Bms HW (ver3.0) and SW (ver4.2.1) and reading over the forums and seeing the different protocol's and problems. I want to make sure I can get this connected to Solar assistant as I have been waiting forever for the beta.


I just sent Pierre a message today asking about a concern I had about Isolation between the DC-DC converter, RPi, and the Jk BMS as they all use the same source power.
I'm also going to be asking about the connection from the Jk BMS to the RPi. I did not buy the RS485 adapter with my BMS so I need to make one up. I did manage to find a JST 1.25/ Molex Picoblade 4 pin plug from and old server SMPS I had laying around. I'm hoping that one of the Amazon purchased USB-TTL or the USB-RS485 will suffice.
 
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