Expanding the System - 48v Racks? Split Phase? Add-Ons?

[DrZ123]

Hi all, planning on expanding the system in a home I am purchasing which is completely off-grid on an island.

There has already been some discussion re additions I would like to make in the home HERE . But need some help with planning the system expansion.

The current system is listed below and can be seen in the photos as well.

My plan is to add battery capacity first, then increase solar, possibly add a second Victron Quattro inverter, and add a propane backup generator.

First step is to add 4x EG4 48v 100ah lithium batteries in parallel with the BBs to increase capacity. Yes, I know mixing and matching batteries isn't ideal, but it seems like the best option currently. See the post linked above for some discussion on that.

For the EG4s in a server rack, do the cables need to be the same length as each cable coming from the 48v blocks of BBs to the red switches? What is the best way to wire that up?

Any and all help much appreciated!
------------------

Current system:
20x 100 panels on room ~2 kW
16x 12v Battleborn lithium batteries @ 100Ah) wired in 48v config ~19.2 kWh
4x 48v battery balancers (on order to be installed to balance the 4 sets of BB batteries)
Victron Isolated DC/DC converter Orion-TR 48 | 12-30
Victron SmartSolar charge controller MPPT 250 | 100 - Tr VE.Can
Victron Quattro 48 volt | 5000 watt | 70 amp charger and inverter
Victron Venus GX communication center

 

[DrZ123]

My first real question is how do I set up the cabling/bus bars for the current BBs and then the additional 4x EG4 48v batteries?

 

[rhovac]

Hi all, planning on expanding the system in a home I am purchasing which is completely off-grid on an island.

There has already been some discussion re additions I would like to make in the home HERE . But need some help with planning the system expansion.

The current system is listed below and can be seen in the photos as well.

My plan is to add battery capacity first, then increase solar, possibly add a second Victron Quattro inverter, and add a propane backup generator.

First step is to add 4x EG4 48v 100ah lithium batteries in parallel with the BBs to increase capacity. Yes, I know mixing and matching batteries isn't ideal, but it seems like the best option currently. See the post linked above for some discussion on that.

For the EG4s in a server rack, do the cables need to be the same length as each cable coming from the 48v blocks of BBs to the red switches? What is the best way to wire that up?

Any and all help much appreciated!
------------------

Current system:
20x 100 panels on room ~2 kW
16x 12v Battleborn lithium batteries @ 100Ah) wired in 48v config ~19.2 kWh
4x 48v battery balancers (on order to be installed to balance the 4 sets of BB batteries)
Victron Isolated DC/DC converter Orion-TR 48 | 12-30
Victron SmartSolar charge controller MPPT 250 | 100 - Tr VE.Can
Victron Quattro 48 volt | 5000 watt | 70 amp charger and inverter
Victron Venus GX communication center

View attachment 163050View attachment 163051View attachment 163052

Wie du das einfach Mal im Büro an die Wand geschraubt hast, herrlich ?

 

[rhovac]

Keep your running system , just add some plexi glass cover at least one of you AC busbars. Prevents fatal accidents with Broomstick Wifes.
Only then I would probably choose an extra charge- inverter unit with some supported batteries and add it parallel on your main AC.
Each AC inverter just tried to keep the voltage and Hz on a good level, so
let them life independent from each other,and both work for the sake of the destiny

 

[DrZ123]

Any easy ways to protect busbar but make it easy to access?

 

[rhovac]

Any easy ways to protect busbar but make it easy to access?

Probably just making a shield and connect it on the busbarmounts or the busbars itself with some distant screws, kind of the style a motherboard is mounted. You could access from the sides then

 

[DrZ123]

So I hooked up one of the battery balancers I got and am getting super weird results. Hooked a POS and NEG cable to each of the terminals on one of the 4s blocks of BBs.

Here's what it read. All 4 batteries in the chain were at 13.2 according to voltmeter.

I tried disconnecting and reconnect battery 4 with no success. Maybe one of the pins in the connector is bent, will have to check that...

But even the voltages are wrong.

 

[rhovac]

I have no experience with such a BMS, but probably there are two effects at the same time. First, the connection of bat 4 has an Issue, and second you the BMS balancing in action and that's why the bat1/2 showing high voltage.
Where did you measure with the voltmeter? Directly on the battery or on the BMS connector?

 

[DrZ123]

I have no experience with such a BMS, but probably there are two effects at the same time. First, the connection of bat 4 has an Issue, and second you the BMS balancing in action and that's why the bat1/2 showing high voltage.
Where did you measure with the voltmeter? Directly on the battery or on the BMS connector?

I tested at the terminals and hooked the balancer up to the terminals...

I know the batteries are wired properly as they have functioned fine for a long time now.

 

[DrZ123]

I tested at the terminals and hooked the balancer up to the terminals...

I know the batteries are wired properly as they have functioned fine for a long time now.

Anyone else have experience with these balancers? Besides the 4th battery not even showing up, why would the voltages on the other three be so off?

 

[DrZ123]

The EG4 will have 4/0 cables from the server rack w 4 EG4 Lifepower4s to the busbars.

The BBs are wired with 2/0 cables to the bus bar from each 4s block

Is that going to be an issue as well?

 

[DrZ123]

Can I daisy chain the batteries with the supplied cables in parallel to the terminals and then just run 4/0 cables from the end pos and opposite end neg to my system? This would be temp until my rack arrives.

Also, can the batteries be used without the RS485 cables connecting them? Mine are on order but don't have them yet.