Hi all. Need some help. I have one multiplus 48/5000/70 already installed on L1 with 3 pylontechs 2.4 kwh. I want to install another multiplus on L2 but with another battery type. I mention that the batteries and the second multi is already bought. Need some help with the instalation. Wiring and config. I mention that I have a fronius symo 7 kw on the in side a smart meter Em24 and a Venus gx.
If that second MP-II will have its own battery, it will have to be totally separate system from the first MP-II. VE.bus interconnection with the first MP-II will not be possible.
It will have to have its own GX controller.
After grid failure those two MP-II system will not be synchronized.
@MarekP as thinking this will have to be the answer. What about the EM24 smart meter and the fronius symo. How they will work with two GX?
If I understand it correctly you have EM24 Carlo Gavazzi meter
https://www.victronenergy.com/live/energy-meters:em24
"Smart Meter" is a Fronius product.
I do not think one EM24 meter can be used by two different GX controllers each running its own ESS assistant. (Someone who knows different could correct me)
I think to run two different ESS assistants you would need two single phase ET112 meters for each phase that have MP-II installed. I could be wrong.
Fronius Symo connected at AC-in would not be affected by two separate MP-II systems but I thing GX controllers should not know about its existence.
You can try to tell about this Fronius only in current GX controller if you need to have zero feed option.
Second GX would need its own ET112 meter if is to run second ESS assistant.
This is so convoluted.
Can you tell me why you decided to buy second MP-II with the different battery instead increasing existing battery and making it all work in a logical manner?
@MarekP I didn't think about this issue... and now I need either to return the batteries or find a workaround to keep them
Did you have a problems with Pylontechs, so you decided to buy different type?
At the beginning I also was considering Pylontechs but decided to build my battery from Winston single cells.
I would suggest that If you can, return the batteries.
Batteries from electric cars are high voltage.
Did you plan to take them apart and connect into 48V package?
I know the guy who bought battery pack from Nissan Leaf, reconnected it as 48V (with Battrium BMS) and is using it with MP-II. Unfortunately they have different chemistry than Pylontech.
Maybe it is possible to connect your new battery in parallel with Pylontechs if you can connect them as 15s pack. Do they have the same chemistry as Pylontech?
@MarekP 
it.s a 9 kwh li ion baterry pack with bms from a hyundai kona 48V
Batteries inside Pylontech are also Li-ion so it could be possible to connect it in parallel.
Just make sure that this Hyundai battery is also 15s pack as the Pylontech is.
There is still a problem with the BMS.
If you just connect this new pack in parallel to Pylontechs, MP-II system will not know the real SOC values and the Hyundai battery would have to have relay to disconnect itself off in case of internal problem.
Pylontech BMS connects with MP-II through VE.Can bus and MP-II is "informed" this way of battery status. It also has dry contact for RTC (ready to charge) and RTD (ready to discharge) signals.
We now nothing about the BMS inside the Hyundai pack and I do not thing it is possible to use it to convey its status to MP-II. Does it have RTC or RTD signals? You have to learn more about it.
If it has RTC/RTD signals you can change the way your Pylotechs talk to MP-IIs (use RTC/RTD signals) and use "2 signal BMS" assistant for Pylontechs and Hyundai batteries connected in parallel. If it does not have those signals, you would have to replace its BMS with something that has them
To know SOC you would have to install SmartShunt.
if you don't feel up to doing it by yourself, I suggest to go with additional Pylontech modules and try to return the Hyundai battery back.
OK, you should confirm that, but from the picture of the battery and schematic of BMS connectors I can see that the Hyundai battery is 15S pack (15 red wires). Unfortunately BMS does not have the RTC/RTD signals.
You can connect this battery in parallel to Pylotechs but you will have to change the way SOC measured. SmartShunt should be used instead.
You will loose the info of the temperature of the Pylontech.
If I were you, I would disconnect VE.can signal from Pylontechs and used their RTC/RTD signals and "2 signal BMS" assistant.
Hyundai battery connected in parallel would take care of itself by internal BMS disconnecting if something is wrong inside.
If you set all the voltages right the BMSes should not intervene during the normal operation. They will react only if there is something wrong inside the battery.
