jgdt

Brilliant. Boer maak 'n plan. My inverter is in garage but this is next to my home office and very eager to reduce the noise for productivity sake.
Could you perhaps share more detail (with links) on the external 12v supply used as well as the sonoff switch?
Would there be a reason to stick with 12V DC fans rather than 230V AC fans? Is it true that the DC fans runs quieter? Just wondering because I don't have a 12V power supply and going the 230V AC fan route might be easier for my case.

Hi, I recently got a SunSynk 8kw inverter installed (and for now linked 10x CS540W and 2x 5.12 Shoto batteries).
My question is around the cooling fans. I understand that they will come on and go off as required for sufficient cooling. But, mine sounds like a bunch of racing cars 'revving' just before they pull away. Its almost like the fans are coming on and off or the speed gets throttled up and down within seconds, like it can't make up its mind.
Is this normal fan behavior?
Attached is a video clip I took yesterday to listen to.
Regards.
SS_Fans 2023-02-06 at 17.11.33.mp4

Hi, I recently got a SunSynk 8kw inverter installed (and for now linked 10x CS540W and 2x 5.12 Shoto batteries).
My question is around the cooling fans. I understand that they will come on and go off as required for sufficient cooling. But, mine sounds like a bunch of racing cars 'revving' just before they pull away. Its almost like the fans are coming on and off or the speed gets throttled up and down within seconds, like it can't make up its mind.
Is this normal fan behavior?
Attached is a video clip I took yesterday to listen to.
Regards.
SS_Fans 2023-02-06 at 17.11.33.mp4

3.46 vs 3.51 means that either the cell has slightly higher capacity than the rest (1 or 2 ah more) or was not properly top balanced. This is nothing to get concerned about, you are probably missing out on 1% (or less) capacity and it is hardly worth the concern.
My lowest cell in my DIY battery is 3.4 vs top one reaching 3.55 and the battery still performs great. 

Will Check if i have photos
The layout looks like this
The left side has 8 cell that are panncaked 
 
And the right has 7 cells
Mine is the 48v 15s model
The 16s 51.2 will just have 8 on the right
And the extra padding gone
 

Yeah, that is cell balancing and it only triggers if the cell is over 3.5V (param 8 ) and there is a difference of 50mV (param 62) between the highest and lowest cell and will stop when the difference reaches 30mV (param 63) or 100% SOC is reached.

Please note that the "overcharging" sub thread herein has been continued under : 
Thanks again for all the help in getting comms going between BMS and PC
 

Maybe not even an issue.  Not sure of the Seplos control logic, but some BMSs do request a 'boost' charge when they need to balance the cells.
You can buy CAN sniffers, or build a simple one with an Arduino and MCP CAN board.

No the Pylon canbus messages are of broadcast type, produced periodically by the BMS, and consumed periodically by inverter. 

Thanks for testing that, it's very helpful to know. So either sunsynk is calling the wrong variable or the bms is sending the wrong variable value when being asked for the charge voltage or maybe seplos is ok with those short spikes in voltage although they are not necessary to fully charge to 100% SOC.
 
Generally I would say yes, but the sunsynk runs so much off SOC he will lose a lot of that functionality. There is another  "Charging overvoltage protection" which is set to 63V, so either it is set that high because it never gets hit due to the total overvoltage protection being triggered first or shoto reckons their batteries can handle 57.8V.
 
I suspect all systems running CAN comms are doing this as I've seen it on another inverter setup.
 
@jgdtI would suggest also contacting the supplier of the battery to see if they will tell you officially that it's ok to be charging to the overvoltage protection. I will bet they are completely unaware of the situation.

Posts from other threads seems to suggest that there's a possible issue w.r.t to SunSynk (possibly limited to just 8kw model) and certain lifepo4 battery makes where the charge voltage is to high effectively overcharging batteries. Instead of overloading those threads further perhaps we can track this here? ...
So far its been reported for Pylontech and Shot, I think both uses Seplos BMS, so this might be the common denominator.
I've also posted on the SunSynk forum:  https://www.sunsynk.org/forum/techical-support/inverter-battery-charge-voltage-too-high about this.
For pylontech refer to onwards:
 
For Shoto refer to onwards:
 

I wonder if this is limited to SunSynk/PylonTech only or a more widespread problem. I have similar problem with 8kw inverter and Shoto SDC10-Box5 (16S) batteries. If I'm not mistaken both Shoto and PylonTech uses SeplosBMS? Perhaps issues is between SunSynk and SeplosBMS somewhere?
Refer to another thread from this post onwards : 
 
I've also posted on the SunSynk forum:  https://www.sunsynk.org/forum/techical-support/inverter-battery-charge-voltage-too-high about this. Will prompt Joel from SunSynk or some tech support tomorrow on it.

Guys, as I requested in the first port, can we PLEASE keep this thread clean and for reporting the latest firmware versions ONLY! There are hundreds of other thread where you can discuss various firmware and technical issues.
Thank you for understanding!

At least you know what is being reported now and it is accurately measuring the cells. I agree with @zivvaanything up to 40deg will be fine. Shoto does class these batteries in their "High Temperature" range and the temp warnings only start at 50deg, protection at 65deg, so I wouldn't worry about it.

Looks to me like some kind of shoto as well. Most probably utilizes the Seplos BMS as well.

Now that I have Battery Monitor comms to my slave battery, thanks to you, I also see the 5 degree difference between cell temp and the ambient temp (battery box inside) reading. Note however that in my case the highest of the 4 cell readings are displayed on the inverter itself as the battery temp, it did not take the higher battery box ambient temp as I was hoping. And it was this temp that worried me in the first place. See screenshot. Garage ambient temp at this time was 26 degrees. So my cells themselves typically gets to +-31 degrees everyday after charging 😞
.

I know this thread is drifting off topic, which was just about the cable and establishing comms, sorry. But, I've proved @jumpertheory on where my inverter is getting the high charge voltage from. I've dropped the overvoltage value in the BMS using Battery Monitor to 56.9V and the inverter followed this and is now showing 56.9V as the charge voltage on the LiBMS page. I'll see tomorrow what happens at charging end, but most hopefully it will charge with 56.9V, then cutout at 56.9V and still throw the error. If this is the case I'll drop it further down to 56.4V to stay in check with the battery's spec. Then my batteries will charge at a more reasonable voltage of 56.4V, but it will still throw errors at the end, but then at least we can ignore the error a bit.
For further reference : https://www.sunsynk.org/forum/techical-support/inverter-battery-charge-voltage-too-high/dl-977cc6ff-2a89-4c5e-9c62-2ed7f4314e37?postId=640b073f6122ae00126b84a6 
PS: I had to change the setting on both batteries before the inverter followed it. To get a hold of master battery I pulled the CAN cable and flipped the DIP switch from 5 to off. Battery Monitor then picked up this battery (but of course then it couldn't get hold of slave battery, but I updated the value there first). Afterwards I restored the dip switch and the CAN cable and all was okay again (at least seems that way).

Adding to previous comment, if this "work-around" does not pan out or causes other issues then I'll have to follow @Antonio de Sa advice of falling back to voltage based settings and not rely Inverter/BMS interaction. At least until SunSynk has somehow resolved this.

I know this thread is drifting off topic, which was just about the cable and establishing comms, sorry. But, I've proved @jumpertheory on where my inverter is getting the high charge voltage from. I've dropped the overvoltage value in the BMS using Battery Monitor to 56.9V and the inverter followed this and is now showing 56.9V as the charge voltage on the LiBMS page. I'll see tomorrow what happens at charging end, but most hopefully it will charge with 56.9V, then cutout at 56.9V and still throw the error. If this is the case I'll drop it further down to 56.4V to stay in check with the battery's spec. Then my batteries will charge at a more reasonable voltage of 56.4V, but it will still throw errors at the end, but then at least we can ignore the error a bit.
For further reference : https://www.sunsynk.org/forum/techical-support/inverter-battery-charge-voltage-too-high/dl-977cc6ff-2a89-4c5e-9c62-2ed7f4314e37?postId=640b073f6122ae00126b84a6 
PS: I had to change the setting on both batteries before the inverter followed it. To get a hold of master battery I pulled the CAN cable and flipped the DIP switch from 5 to off. Battery Monitor then picked up this battery (but of course then it couldn't get hold of slave battery, but I updated the value there first). Afterwards I restored the dip switch and the CAN cable and all was okay again (at least seems that way).

31° is absolutely not an issue but is more or less an expected temperature when charging. You could start to worry above 40° ...

@jgdt Sorry I'm not familiar with SunSynk inverters, Maybe contact them and ask what you must do to run your system without battery BMS coms, until such time they fix that bug. I personally run my system without BMS coms, I like to control my battery using voltage settings, that way I know that I'm looking after my battery to the best of the OEM recommendations. 

That is excellent news, so the adapter works finally!
That's a very good question, I have not seen anyone with this working yet, I've not tried as my inverter doesn't support CAN and I only have 1 battery so DIP addressing wouldn't be an issue.
I think you are correct that the software is seeing the slave as pack1 because DIP 1 is on. There are files on the seplos google drive for DIP settings for CAN and RS485 and comparing them it looks like DIP 5-8 on the master are used to set the CAN address (or number of batteries) and DIP1-4 are used to set up the RS485 addresses.
The RS485 doc shows that with multiple batteries DIP1 needs to be set on the master and DIP2 on the slave which is why it is seeing your slave as the master in the software because it has DIP1 on from the CAN setting and it can't see your master because it has no (or incorrect) DIP setting for RS485 because DIP1-4 are all down. I assume that it sees DIP1 as master then it looks for the next address for the slave which should be DIP2 up.
So after scratching my head for a while I think the best would be to try the following DIP settings to satisfy the CAN addressing requirement and also the RS485 addressing requirements to get them to work at the same time:
Master: DIP1 on (set as master for RS485) and DIP5 on (set as master of 2 batteries for CAN)
Slave: DIP2 on (set as slave for RS485) [no need for CAN setting, it will speak RS485 to the master]
This is something I noticed before on someone else's setup. It seems that with comms the BMS requests a charge voltage of +57V and the BMS is set to protect at 57.75V. I really don't know why it is set so high because I easily charge my battery at 56V.
Yeah the bms controls the current request nicely, but unfortunately it requests a high voltage, so it's possible it might hit that just for a short time at the top of charge and also by then the amps will be low anyway, so maybe not much damage, but I don't like seeing a red error message. You can pull up the history which should give you some decent info to be able to see what was going on and what voltages were reached.
It will clear after it reaches 53.5V again.

I have the Shoto SDA10-48100 5.12kWh (16S) which looks identical to the SDC10, just that it is rack mounted instead of stacked. I'm pretty sure they will use the same seplos BMS.
P.S. I just checked the manual you uploaded and it is almost exactly the same. Pinouts etc. are identical. The only difference I see is that the SDC10 is 80% DOD whereas the SDA-10 is 90% DOD.
P.P.S Looking closer I see that the SDC10 is also rack mountable, the housing is identical to the SDA-10 and I also see it advertised as 90% DOD... seems like the same battery to me.

Unfortunately I can't, I have heatshrink over it to strengthen the join to the wires. If it says CH340 on it then it must be CH340. I read that the CH340 chips don't work so well which is why I had given up on mine but saw someone else get it working on another battery so I gave it another try. If you see data with the CH340 driver and not the FTDI then I guess it is CH340.
2.1.8 was the only version around when I bought my battery and it works so I've not tried anything else. I think 2.1.9 is the latest. The CH340 chips and drivers are older than the FTDI so it should work with 2.1.8 if it is going to.
Sorry I can't help any further as I don't have experience of a working CH340 adapter, so I can't say for sure if it will work or not.

Guessing that there are 4 cell groups (with 4 cells each for 16S), so one temp reading per cell group?