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durandetantoine avatar image
durandetantoine asked

Multiple MPPT with BMS

Hi all. I have a multiplus 2 GX and pylontech 48v bank with bms.

The system works well with one string at the moment. The bms controls the MPPT via DVCC. The MPPT is connected via cable to the inverter.

I am adding 2 more strings with 2 new MPPT100/20. I can smart network the new MPPT via Bluetooth. My question is: how do I make sure the bms still controls the MPPT since I cannot impose which MPPT is the master? Do I have to physically connect all MPPT via cable (VE direct I think) or can I use the bluetooth network?

Many thanks for the answers.

MPPT SmartSolar
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3 Answers
mje avatar image
mje answered ·

I have a similarish problem, two MPPT 100/50's and a BMV-712.... There are only two VE.Direct slots on the Color Controller - so I have the BMV and one MPPT connected via two VE.Direct cables. I also set up a BlueTooth network to combine all three devices. However, the Color Controller only see's the one MPPT as does https://vrm.victronenergy.com. I think you'll need to wire everything - there is a VE.Direct to USB device cable available, and you can scale the available USB up with a powered USB hub. PITA - when I think BlueTooth should do that job. The BlueTooth network just currently shares a few values - which does include the battery temperature via the BMV sensor.


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nickdb avatar image
nickdb answered ·

Smart networking does not work for the ESS use case.

You can use the USB port and attach it to a USB hub, from there USB-> VE.direct cabling.

There is plenty of info about this in the GX/product docs.

The internal GX has limited connectivity, it's best to use an external cerbo if you were planning to expand to such an extent.

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Joe avatar image
Joe answered ·

I have two similar MPPTs, each connected via VE.direct to USB cable with my Venus on a Raspberry.

BMS is a REC BMS 16s.

So far everything works well, BUT:

- 1-2 times per day I get an error for one of the devices "Connection to BMS lost", Error 67

- it's not always the same MPPT, one time it's A, next time maybe B

- only connecting via Bluetooth and set back to standard immediately resolves the isse.


1664999022026.png

Does anybody have a clue why this is so? The error comes regular and seems to be a real issue.


1664999022026.png (32.5 KiB)
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