Connect home made lifepo4 battery banks to the Victron cerbo GX

Modifications
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1

Good morning.

I need help please. I have made my own battery banks using JK BMS V19. I have tried to connect the batteries using the Ethernet cable provided with the BMS. I can’t seem to get them to talk to each other. Can you let me know where I have to put the Ethernet cable in the communication interface board. Do I use the can or the RS485 port? On the display screen on the battery it does not show the other bank of batteries? How do you set them up on your phone app? I also need help with the pins. How do I set the slave or master battery up and then the rest to 12 as I have 12 batteries in total. Which cable do I use and port to connect the Ethernet cable to the cerboGX either type A or B. Where do I plug the Ethernet cable into the cerboxGX please.

My system is 24volt with a multi plus ll 5000w

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diy Yixiang batteries with pre- build in jk v19 bms..

Victron type A canbus cable to the Cerbo mk2

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3

Why didn’t you use pre build 24 volt (empty) battery boxes from Yixiang or other suppliers? And why 24 volts and not 48 Volts?

4

Are there no fire safety regulations in your country?

5

Morning Gary. Welcome to the Victron community forum. From the other side of the pond.

Ok. We need you to tell us the firmware revision on the JK BMS boards (all the same?) and what to BMS-can-protocol is set to in your Cerbo GX device.

Also note the dipswitch settings that @Frisianstar shared here in his pictures.

As for the DIY RJ45 cable. BMS side: 2, 7, 8 and on the Cerbo side: 3,4, 5

6

I would seriously reconsider using proper steel casings, wooden housings are a bad idea for fire risk and are unlikely to pass any regulatory safety requirement in a first (or second) world country.

There are various topics here about this BMS which is a good starting point.

It is concerning that at this stage such basic questions are being asked, this is freely available information, if the relevant manuals and free, online training are consulted..

I would encourage you to consult a professional to help with the build. As a Victron forum we try to encourage best practices to ensure safety and to avoid disappointment.

7

Did you electrically isolate the individual cells from one another with an interlayer??

If not, you have a serious problem just waiting for the thin outer foil to be damaged. If the outer foil is damaged, the cell potential can arc through. In that situation, I wouldn’t want to be in the room with the batteries (it’ll get bright and loud!!)

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Hi Karl. Yes I did on all of them

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Hi Nick. I asked my supplier who I bought the stuff off and his reply was he doesn’t have a clue with 3rd party BMS systems. This is why I’ve asked on this platform.

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Hi BAnders. I will check tonight and get back to you. They are in an off grid cabin. Thank you for answering my question

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Hi Frisandstar. Thank you for the pictures. I have done in the pictures. It still did not work. So I’m am still doing something wrong.

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What have you done and installed or programmed so far?

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Read this post:

Www.diysolarforum.com may be usefull, a lot of topics about the jk bms v19

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Hi Karl Heinz have changed the settings to this in the pictures. I have the dip switches right. So I know I’m doing something wrong.

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Still waiting for your Cerbo communication settings.