EG4 6500 battery communication w two banks

[offgridfarmgineer]

I have 12 EG4 Lifepower batteries and two EX6500 inverters for split phase power. I'm using two racks of 6 batteries, one supplying DC to one inverter, and the other supplying to the other one, each with their own DC disconnect and each feeding one phase to my main breaker panel. I'm wondering for communications if I need to treat them as one bank of 12 and have one longer Ethernet cable running between battery 6 and 7 from rack to rack and then one connection to the master inverter (and no bms connection to the slave inverter). Or do I address them 1 through 6 (twice) and connect the supplied black Ethernet from each bank to each communication port on each inverter.
Thanks

 

[Adam De Lay]

I have 12 EG4 Lifepower batteries and two EX6500 inverters for split phase power. I'm using two racks of 6 batteries, one supplying DC to one inverter, and the other supplying to the other one, each with their own DC disconnect and each feeding one phase to my main breaker panel. I'm wondering for communications if I need to treat them as one bank of 12 and have one longer Ethernet cable running between battery 6 and 7 from rack to rack and then one connection to the master inverter (and no bms connection to the slave inverter). Or do I address them 1 through 6 (twice) and connect the supplied black Ethernet from each bank to each communication port on each inverter.
Thanks

Per the manual, you should have the two banks connected together, both from the DC side and the comms side.

“WARNING! All inverters of a system must share the same battery bank. Ensure all batteries are connected to common bus bars, with equal cable lengths between both the batteries/bus and inverter/bus connections.”

Then you connect the primary inverter to your battery bank and set option 5 on that inverter to EG4, then on your slave inverter you set option 5 to USE.

 

[offgridfarmgineer]

Thanks. Yeah I guess I might have some unbalanced legs which could be an issue over time, mostly used for 240v EV charging but have a mini split and cool bot on 120 too. Just seems weird to bring separate bank leads to a terminal strip and then separate again (like an X) to the inverters but is logical.

Per the manual, you should have the two banks connected together, both from the DC side and the comms side.

“WARNING! All inverters of a system must share the same battery bank. Ensure all batteries are connected to common bus bars, with equal cable lengths between both the batteries/bus and inverter/bus connections.”

Then you connect the primary inverter to your battery bank and set option 5 on that inverter to EG4, then on your slave inverter you set option 5 to USE.

 

[Adam De Lay]

Thanks. Yeah I guess I might have some unbalanced legs which could be an issue over time, mostly used for 240v EV charging but have a mini split and cool bot on 120 too. Just seems weird to bring separate bank leads to a terminal strip and then separate again (like an X) to the inverters but is logical.

I’m guessing the reasoning behind it is due to the fact that the inverters work together in a pair. If one goes down, they both will. So if your inverters are unbalanced and one shuts down due to a low battery, the other one will as well because it lost communication.

 

[offgridfarmgineer]

Luckily I bought some current connected busbars from my plan A, then wasn't going to use for plan B and now can use for plan C haha. I'll post up pics since I used all conduit and wireway for a neat set-up. Weird that the manual doesn't even mention the neutral screw issue (I bought mine a and batteries a year ago, taking along time due to constructing a whole building etc) nor what the black jumper and fuse are for that come in the CD bag. I pulled the screw in each and will update the firmware to the latest in any case.

 

[Adam De Lay]

Luckily I bought some current connected busbars from my plan A, then wasn't going to use for plan B and now can use for plan C haha. I'll post up pics since I used all conduit and wireway for a neat set-up. Weird that the manual doesn't even mention the neutral screw issue (I bought mine a and batteries a year ago, taking along time due to constructing a whole building etc) nor what the black jumper and fuse are for that come in the CD bag. I pulled the screw in each and will update the firmware to the latest in any case.

Actually, with the latest firmware, you don’t have to do anything with the screws anymore. There’s a menu option (42) which controls it all.

The fuses are replacements for an internal fuse on the positive battery connection. It’s actually located under the upper lid, directly above the positive battery terminal.

Not sure what your referring to as the “black jumper” unless your taking about the black USB to Ethernet cable used for battery comms?

 

[offgridfarmgineer]

Actually, with the latest firmware, you don’t have to do anything with the screws anymore. There’s a menu option (42) which controls it all.

The fuses are replacements for an internal fuse on the positive battery connection. It’s actually located under the upper lid, directly above the positive battery terminal.

Not sure what your referring to as the “black jumper” unless your taking about the black USB to Ethernet cable used for battery comms?

Yes I saw that but decided just to pull them since I'll never need it grounded and perhaps it didn't work for me.

I didn't see that fuse there, maybe different color or something I'll look again . There is something that looks like the fuse and same size (roughly?) but just all thin metal. Should fire up Wednesday so we'll see.