diy solar

diy solar

Seplos BMS and RS485 coms to PC

Annoying thing is that I can see the TXD light flash in the software (using COM3) both baud rates and then the ERR light flashes shortly afterwards.
I leave dip 1 on the first battery. For some reason, the software does not like all off. The Solar Assistant software also calls for dip 1 on the first battery.

I made a portable connector that works though, using a standard patch cable and usb adapter.

Make sure pin 1 goes to B, and pin 2 goes to A.

The little RJ45 breakout module makes it much simpler than trying to make your own cables. Everything is from Amazon.
 

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I leave dip 1 on the first battery. For some reason, the software does not like all off. The Solar Assistant software also calls for dip 1 on the first battery.

I made a portable connector that works though, using a standard patch cable and usb adapter.

Make sure pin 1 goes to B, and pin 2 goes to A.

The little RJ45 breakout module makes it much simpler than trying to make your own cables. Everything is from Amazon.
Thank you, sincerely appreciated! I'm starting to think that there might be a problem with the BMS itself.

I've grabbed another laptop but I can't even get the port to work on that, let alone select it in the software (installed the driver from the download on Seplos website). I'm reluctance to pay £25-30 for the official Seplos dongle, so will either have to test when the next box arrives (see if the 10E BMS in that works with my laptop) or just rely on the app alone which seems ridiculous.

It's probably something really simple, but I'm not finding it although following all the instructions from good people like yourself on this thread. Thanks again?
 
Thank you, sincerely appreciated! I'm starting to think that there might be a problem with the BMS itself.

I've grabbed another laptop but I can't even get the port to work on that, let alone select it in the software (installed the driver from the download on Seplos website). I'm reluctance to pay £25-30 for the official Seplos dongle, so will either have to test when the next box arrives (see if the 10E BMS in that works with my laptop) or just rely on the app alone which seems ridiculous.

It's probably something really simple, but I'm not finding it although following all the instructions from good people like yourself on this thread. Thanks again?
It took me a while also. I also had a bad BMS that did not communicate, and replaced it.
That said, once connected together, and monitored with Solar Assistant, its easy.
 

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I just went through this fight too.
You have to use the RS485 daisy chain connector on battery #1, not the RS/CAN port. Data rate is 19,200 despite what you see everywhere else.
Battery #1 has to be #1, not #0...that is for the monitor software.
It also needs to be told how many other batteries there are via switches 5-8.
I can now see them all in either SA or battery monitor, just have to switch the RS485 dongle between the 2 systems.
 
It took me a while also. I also had a bad BMS that did not communicate, and replaced it.
That said, once connected together, and monitored with Solar Assistant, its easy.
Fixed! Grabbed a coffee, said I wouldn't look at it again today but couldn't help myself?. Found yet another port driver (google search again to others having the issue) and after double checking the adapter had the right chipset for RS485 (which shavermcspud had already pointed out by sharing the RS485 adapter I'd bought), used the universal windows driver on here > https://www.silabs.com/developers/usb-to-uart-bridge-vcp-drivers?tab=downloads which created a new comms port. Selected new port in software and didn't work on 9600, then tried again once changed to 19200 (in Win + software) and BINGO! I feel like I've won the lottery?.

shavermcspud recommended RS485 adapter + standard straight-through ethernet cable cut/stripped using pins 6/7/8 (as directed in this thread) + windows driver above = happy and connected me!

Thanks again for your help on this. I'll need to find the appropriate thread to learn about solar assistant as you've fully grabbed my attention with that now I've been released from the RS485 connection pit!
 
I just went through this fight too.
You have to use the RS485 daisy chain connector on battery #1, not the RS/CAN port. Data rate is 19,200 despite what you see everywhere else.
Battery #1 has to be #1, not #0...that is for the monitor software.
It also needs to be told how many other batteries there are via switches 5-8.
I can now see them all in either SA or battery monitor, just have to switch the RS485 dongle between the 2 systems.
Thank you! I've only got the one pack at the moment (other heading over from China now). Completely agree with your reference to a fight, it's such a battle for something that should be simple (in my mind anyway). I'll connect up using the RS485 ports on both boxes (parallel) and use the CAN for inverter? Cheers
 
Here is my setup....those frigging LED's will take your eye out kid !!!!
 

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Here is my setup....those frigging LED's will take your eye out kid !!!!
Awesome! That's a serious amount of storage. I'll need to save my pennies to expand beyond the two (when the 2nd arrives). It's all about the dip switches...
 
Hi,

I had a similar issue in connecting my PC to BMS v3.
Was trying the RS4851 port, had a cable from Fogstar - didnt work
Ordered the WINGONEER USB 2.0 to RS485 Serial Converter Adapter
Wired that up as per this post - still no joy.
In the end out of pure frustration I just plugged into the rs4852 port - hey presto - it worked - connected no issue.
The Fogstar cable worked in that port too.

I was always under the impression that the rs4852 port was for comunication with another battery pack?
Am I wrong.
 
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