multiplus-ii and PACE bms

[theimportanceofbeing]

Hi I am just setting up my new prebuilt fogstar LiFePo4 battery , 48v 15.5kwh , eve cells , PACE BMS & JK Active Balancer

Fogstar battery link


I am connecting it to my Multiplus-ii 48/10000 , I have not got a Cerbo or any victron connectivity systems

I've spoke to fogstar they said to follow these instructions , but I don't understand how or where I get the Battery BMS to communicate with the multiplus . It says the BMS needs to send a signal to the inverter to tell it when to stop charging

How does this work ? Can anyone point me in the right direction please

https://www.victronenergy.com/upload/documents/Manual-Connecting-other-lithium-battery-systems-to-Multis-and-Quattros-EN.pdf

 

[sunshine_eggo]

The only way to make a BMS COMMUNICATE with a Victron inverter via the protocols mentioned is with a GX device. The communication entails telling the system what the Charge Voltage Limit (CVL), Charge current limit (CCL) and discharge current limit (DCL) and gives the BMS control of the GX connected devices.

What you have are the instructions for simple triggering the MP's inputs.

Your battery must have a relay that can open and close based on BMS trigger events - preferably TWO for charge/discharge separately. You must connect this relay(s) as described in the document, properly configure the battery relay behavior and load/configure the assistant.

Basically, the BMS keeps the circuit closed when everything is fine and opens it when it wants to disable charge, discharge, or both.

Sounds like you're getting some really crappy support. Based on the manual, I don't see that the battery can communicate with the inverter via the two-signal BMS method as it has no contactors/relays. You MIGHT be able to open the battery up and find something on the BMS itself.

From the manual:



You need a GX device and connect via the CAN port for battery communications.

 

[theimportanceofbeing]

The only way to make a BMS COMMUNICATE with a Victron inverter via the protocols mentioned is with a GX device. The communication entails telling the system what the Charge Voltage Limit (CVL), Charge current limit (CCL) and discharge current limit (DCL) and gives the BMS control of the GX connected devices.

What you have are the instructions for simple triggering the MP's inputs.

Your battery must have a relay that can open and close based on BMS trigger events - preferably TWO for charge/discharge separately. You must connect this relay(s) as described in the document, properly configure the battery relay behavior and load/configure the assistant.

Basically, the BMS keeps the circuit closed when everything is fine and opens it when it wants to disable charge, discharge, or both.

Sounds like you're getting some really crappy support. Based on the manual, I don't see that the battery can communicate with the inverter via the two-signal BMS method as it has no contactors/relays. You MIGHT be able to open the battery up and find something on the BMS itself.

From the manual:

View attachment 289790

You need a GX device and connect via the CAN port for battery communications.

Thank you for getting back


Is it safe to just run without communications ?

 

[dmsims]

Honestly just buy a Cerbo (mine was an unsued unit from ebay - £140)

 

[theimportanceofbeing]

Honestly just buy a Cerbo (mine was an unsued unit from ebay - £140)

It's tempting !

I think they're a load of cables I need to buy too though @sunshine_eggo very kindly explained it all in detail in this thread:---

T

Thread 'Can someone explain Victron Cerbo to me like I am an idiot ?'

Dec 30, 2024

Hi , would someone please be willing to explain Victron Cerbo GX mk2 to me like I am a idiot ?



I have multiplus 48/10000
Smart solar 250/100
Bmv-712 shunt

Looking at buying a Fogstar 15.5kwh battery

Fogstar says I need a Cerbo GX to link the battery to the inverter , and a "type B Victron battery BMS to VE CAN cable"

Fogstar Energy 16.1kWh 48V Solar Battery

The Fogstar Energy 16.1kWh 48V Solar Battery delivers exceptional value for money, being the most affordable battery of its capacity in the world.

www.fogstar-energy.co.uk

Is this simple to do ? Can this link all my different victron kit together ? Am I going to struggle

• theimportanceofbeing
• Replies: 29
• Forum: DIY Solar General Discussion

 

[dmsims]

For the Multiplus you just need an ethernet cable

Solar, shunt - ve.Direct cable

 

[sunshine_eggo]

Yep.

MP to GX - ethernet
Shunt/MPPT to GX - ve.direct
BMS to GX - ethernet
VE.CAN MPPT - ethernet

GX devices are awesome. I didn't implement my CCGX for the first year. My world expanded exponentially afterwards. Once I had remote access, my confidence level went through the roof.