Seplos CAN BUS RS485 48v 200A 8S-16S BMS

[Sanwizard]

My batteries have been sitting around also since I have moved, so I bought a LiFePo4 charger to fully charge and balance all the cells before putting them in parallel together. You can get a similar one signature solar sells by going direct via Alibaba. Mine is actually a higher amperage for a lower price.

It looks like this one:

48V Waterproof Lithium Battery Charger

Allied 48V Snap Plug Waterproof Lithium Battery Charger 15A Key Features: 48V 15A Designed to work perfectly with 48V Allied lithium batteries Great - Allied Lithium Golf Cart Batteries

alliedlithium.com

This is the 22 amp version for $189 plus shipping.

 

[Lt.Dan]

Yes I discovered those about 18 months ago and have the 30a model. Picked it up for $145/shipped if I remember correct. ?

 

[Sanwizard]

Yes I discovered those about 18 months ago and have the 30a model. Picked it up for $145/shipped if I remember correct. ?

Damn good price!

 

[Lt.Dan]

Damn good price!

I just went way back in time and found the post. You were even part of the thread! I stand corrected that it is the 25a model and was $160 after shipping and fees. Works great though.

48v Battery Charger?

I received the charger today. Not stoked with the packaging, but it made it here okay, so I cant complain. 1 piece of foam on top Charger with no packaging around it. Charger itself. I opted for ring terminals. Some nice heavy duty wiring. Specs. Nice power factor, and high...

diysolarforum.com

 

[Sanwizard]

I just went way back in time and found the post. You were even part of the thread! I stand corrected that it is the 25a model and was $160 after shipping and fees. Works great though.

48v Battery Charger?

I received the charger today. Not stoked with the packaging, but it made it here okay, so I cant complain. 1 piece of foam on top Charger with no packaging around it. Charger itself. I opted for ring terminals. Some nice heavy duty wiring. Specs. Nice power factor, and high...

diysolarforum.com

Too funny. I should have bought it back then. I still have the Riden, but it takes forever.

 

[Lt.Dan]

I re-read this thread yesterday, and the question still stands. Did anybody design a 3D Printable enclosure for these BMS's?

EDIT: Wow i can't believe I actually found something for the BMS on Thingiverse: https://www.thingiverse.com/thing:5265259

It doesn't cover the whole thing, but it includes stand offs, and mounts the Display screen right to the front, and it all snaps on! Gonna try and print it tonight and see how it comes out. Getting correct hardware might be tricky, but we'll see.

 

[deonbez]

@Lt.Dan, my son is in the process of finalizing a 3D design for a Seplos BMS enclosure.
It comes in smaller sections for easier printing. There are still some small adjustments required.

Will share it when complete.

 

[Lt.Dan]

I finished the print from Thingiverse. My print quality isn't the greatest, and need to work on a few things (I don't do it very often, and am still learning). But it fits the BMS good, and clips on pretty well. The buttons on the screen dont line up very well, which is preventing the screen from sitting flat at all. Might be able to just take a small dremel and oval the holes a bit to fit better. All in all, its not bad.









@deonbez Very excited to see yours when completed. I would also kind of like to see some ventilation for the heat sink in yours? Not sure if the heat from the heat sink will warp/distort the PLA. Unless your printing it with Nylon or ABS?

 

[Sanwizard]

I finished the print from Thingiverse. My print quality isn't the greatest, and need to work on a few things (I don't do it very often, and am still learning). But it fits the BMS good, and clips on pretty well. The buttons on the screen dont line up very well, which is preventing the screen from sitting flat at all. Might be able to just take a small dremel and oval the holes a bit to fit better. All in all, its not bad.

View attachment 118215
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@deonbez Very excited to see yours when completed. I would also kind of like to see some ventilation for the heat sink in yours? Not sure if the heat from the heat sink will warp/distort the PLA. Unless your printing it with Nylon or ABS?

 

[Lt.Dan]

Trying to get communication is turning out to be just as difficult as I had figured.

Seplos emailed me a firmware update for the Deye, and they said it should work with Sol-Ark as well, which flashing the firmware went smoothly. But in the Battery Monitor app it won't let me set a Can protocol. I've tried setting it to the PN-GDLT, but I just get an error saying it didn't work. Can't figure this part out?

I've tried the wiring configuration suggested in this post https://diysolarforum.com/threads/seplos-can-bus-rs485-48v-200a-8s-16s-bms.20051/post-300832, I've also wired the BMS Side in both Canbus and RS485 like shown in their manual, and the same for the Sol-Ark side based on their manual, which is surprisingly the same wiring.






I also am a little unsure of which BMS Lithium Batt Modes to select in the Sol-Ark. I assume 00 or 02? If its 02 for Pylontech, which is labeled Modbus, do I need to connect the cable to the Modbus RS485 port on the inverter? And not the Canbus port?

 

[Lt.Dan]

I even just tried to follow their pinouts exactly and this is what I have:

For the Sol-Ark, Pin 4 - Can HIGH, 5 - Can LOW, and 6 - Ground,


And then for Seplos, Pin 4 - Can LOW, Pin 5 - Can HIGH, Pin 6 - GROUND.




After crimping and testing, still nothing.

 

[houseofancients]

Trying to get communication is turning out to be just as difficult as I had figured.

Seplos emailed me a firmware update for the Deye, and they said it should work with Sol-Ark as well, which flashing the firmware went smoothly. But in the Battery Monitor app it won't let me set a Can protocol. I've tried setting it to the PN-GDLT, but I just get an error saying it didn't work. Can't figure this part out?

I've tried the wiring configuration suggested in this post https://diysolarforum.com/threads/seplos-can-bus-rs485-48v-200a-8s-16s-bms.20051/post-300832, I've also wired the BMS Side in both Canbus and RS485 like shown in their manual, and the same for the Sol-Ark side based on their manual, which is surprisingly the same wiring.

View attachment 118317

View attachment 118318


I also am a little unsure of which BMS Lithium Batt Modes to select in the Sol-Ark. I assume 00 or 02? If its 02 for Pylontech, which is labeled Modbus, do I need to connect the cable to the Modbus RS485 port on the inverter? And not the Canbus port?

you should use 00 for deye/sol-ark/sunsynk.
also be aware that the pinout for canbus and modbus (rs485) is different.

don't forget to reset the bms after changing the mode ( reset button)

 

[Lt.Dan]

you should use 00 for deye/sol-ark/sunsynk.

Perfect. Thank you.

also be aware that the pinout for canbus and modbus (rs485) is different.

Yes, I have tried the Canbus pinout, and the modbus pinouts. The pictures from above are for the Canbus pinouts.

don't forget to reset the bms after changing the mode ( reset button)

THIS is something that isn't notated anywhere in any manuals! I will try this.

I'm awaiting an answer from Seplos as to why changing the CAN protocol inside Battery Monitor app throws an error.

 

[deonbez]

I finished the print from Thingiverse. My print quality isn't the greatest, and need to work on a few things (I don't do it very often, and am still learning). But it fits the BMS good, and clips on pretty well. The buttons on the screen dont line up very well, which is preventing the screen from sitting flat at all. Might be able to just take a small dremel and oval the holes a bit to fit better. All in all, its not bad.

@deonbez Very excited to see yours when completed. I would also kind of like to see some ventilation for the heat sink in yours? Not sure if the heat from the heat sink will warp/distort the PLA. Unless your printing it with Nylon or ABS?

@Lt.Dan : Nice print in red (aka be careful / danger)!
I asked my son to add a ventilation area for the BMS heatsink
Will share a photo as soon as I have printed the refined 3D design

 

[Swing]

How does paralleling them work? If one of the batteries has a problem, it takes them all down?
Or if not, how does it deal with a battery coming online later again with a different state of charge and voltage?
I mean if you build some NMC 10kWh blocks, than a lot of power can be flowing between them if they are not kept in balance (because one has been closed for a while due to some issue)

 

[championc]

Here is my cable connected to a standard Cat5 Patch Lead

A+ to the White/Brown
B- to the Brown
Gnd to the Green
Gnd to the White/Green

It SHOULD work with any RS485 to USB dongles from Amazon

 

[deonbez]

@Lt.Dan : Nice print in red (aka be careful / danger)!
I asked my son to add a ventilation area for the BMS heatsink
Will share a photo as soon as I have printed the refined 3D design

@Lt.Dan, the 3D design for the Seplos BMS is complete and available at https://www.thingiverse.com/thing:5604549
Top is currently printed with Carbon Fibre infused PLA, bottom with PETG. Will see if another material is required.

 

[houseofancients]

@Lt.Dan, the 3D design for the Seplos BMS is complete and available at https://www.thingiverse.com/thing:5604549
Top is currently printed with Carbon Fibre infused PLA, bottom with PETG. Will see if another material is required.

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good job, nice work

 

[Lt.Dan]

I am still having a hard time with the comms from Seplos to SolArk, and I'm starting to think its because of the RS485 BMS I have.

Seplos doesn't seem to think that it is a problem, and the firmware flash I put onto it is why I cannot change the communication protocols in the Battery Monitor software, it is locked to the Deye comm protocol now.

I have the documentation from seplos and Sol-Ark as the following:




And this is how I currently have my RJ45 cable connected:
Seplos Pin 4 to SA Pin 8 (BLUE WIRE)
Seplos Pin 5 to SA Pin 7 (BLUE/WHITE WIRE)
Seplos Pin 6 to SA Pin 6 (ORANGE WIRE)


Can anybody tell me if I'm doing something wrong?

 

[duyvietstar]

I am still having a hard time with the comms from Seplos to SolArk, and I'm starting to think its because of the RS485 BMS I have.

Seplos doesn't seem to think that it is a problem, and the firmware flash I put onto it is why I cannot change the communication protocols in the Battery Monitor software, it is locked to the Deye comm protocol now.

I have the documentation from seplos and Sol-Ark as the following:
View attachment 119039

View attachment 119040

And this is how I currently have my RJ45 cable connected:
Seplos Pin 4 to SA Pin 8 (BLUE WIRE)
Seplos Pin 5 to SA Pin 7 (BLUE/WHITE WIRE)
Seplos Pin 6 to SA Pin 6 (ORANGE WIRE)
View attachment 119041

Can anybody tell me if I'm doing something wrong?

For seplos port, you have to count backwards.