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EG4 LL (V2) Multiple Racks Fusing???

WattAboutThat

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I am trying to understand if fusing is required between multiple parallel racks of batteries:

My hypothetical:

If I have, for example, FOUR (4) Full,
48V EG4 LL (V2), battery racks.
Each rack to be connected to a common
bus bar, then bus bar connected to multiple inverters (in this case 18kPV inverters),

Does each battery rack need a fused connection to the bus bar, or any other protection, to isolate one rack from another, in the event of a short or other unknown issue?

Assume there are fuses between the inverters and the bus bar.

Thanks for your feedback.
 
I am thinking at some point to get another EG4 LL V2 (6) battery server cabinet to add to my existing one. I know I'll need a positive and negative busbars. Anyone know of what size I would need even if I added a 3rd fully populated server rack for a total of 90ah of storage? Are there any busbars anyone would recommend please for this expansion project I have yet to kick off??
 
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I am thinking at some point to get another EG4 LL V2 (6) battery server cabinet to add to my excising one. I know I'll need a positive and negative busbars. Anyone know of what size I would need even if I added a 3rd fully populated server rack for a total of 90ah of stoage? Are there any busbars anyone would recommend please for this expansion project I have yet to kick off??
It is load dependent; you try to size your fuses as low as possible, but high enough that they would not risk nuisance tripping. 300A each rack is likely on the high end; 200A on the low end in general terms.
 
So 600 Amp busbars? I do have an ev so I think top draw could be 100 amps if I get another Solark 15k in the future. It's rare, however for future proofing wanted to make sure I was covered on the battery capacity side.
 
So 600 Amp busbars? I do have an ev so I think top draw could be 100 amps if I get another Solark 15k in the future. It's rare, however for future proofing wanted to make sure I was covered on the battery capacity side.
If your peak draw is expected at 100A (48V) (in the future), then just use each cabinet at 100A. DC input for a SA15k is ~250A though, so that would be the minimum recommended for a single cabinet to single inverter. Three cabinet to two inverters could drop to 200A each, but limited gain.

With the busbar set up as B-I-B-I-B (battery/inverter) then 600A is plenty.
 
If your peak draw is expected at 100A (48V) (in the future), then just use each cabinet at 100A. DC input for a SA15k is ~250A though, so that would be the minimum recommended for a single cabinet to single inverter. Three cabinet to two inverters could drop to 200A each, but limited gain.

With the busbar set up as B-I-B-I-B (battery/inverter) then 600A is plenty.
Thanks
 
Wound up getting a victron 1000amp busbar. The cool thing is you can add multiples, as your battery banks grow if needed. One should take care of 2 separate server racks.

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Wound up getting a victron 1000amp busbar. The cool thing is you can add multiples, as your battery banks grow if needed. One should take care of 2 separate server racks.
The only thing to be careful of is the fuses are not rated for an especially high fault current (IIRC).
 
The one I have does not have any fuses.
A little late to the party, but I also have the lynx power in that connects a rack of eg4ll-v2 and 2 eg4 6500. I installed 2 MEGA fuses (victron 200A 58V) in it for the inverters wires as shown in
. If I ever add another battery rack, I'll add fuses for both of them too.
 
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