LG RESU10H Secondary: ISO or how to convert Primary info

[warx]

Hi, I have two RESU10H Primary batteries (SEG1) installed with SolarEdge 7600H and BUI. Been stuck with it since installers messed up in 2022 and the Gen 2 RESUs were discontinued. If anyone had a lead on a Secondary (SEG2) unit in any state (prefer healthy!) or if anyone knows a way to convert/fool a Primary to uss Modbus ID 14 (instead of hardcoded 15) I would love to hear.

TIA - Mike.

[Amsters]

Hi Mike,

Did you make any progress on this. I recently bought 2 new Resu10H units for $600 each but there are only SEG1 units available. My unit is working fine as a single ESS , the second unit is for my sons ESS but I'm hoping to use it initially to try and get it working as a SEG2 . If I succeed I'll buy another for my system . Like you I checked the serial on the LG recall tracker before buying them and they are all okay, the mfr dates are all 2022 so pretty much the end of the production before they replaced it with the 10/16H Prime.

I also bought a broken Resu10H complete with cells for $130, also recall clear made in 2022 ! The DC -DC converter blows the main 60A DC fuse at power on . I'm going to dismantle the converter and take a look at the components around the modbus port area , maybe there is a dip switch or a link block that allows the device address to be set. If I can't find any such option I'm thinking of a Raspberry PI project that would sit in front of the second units modbus port and spoof it as ID 14 , it could strip the address 14 header from the modbus data and readdress (aka spoof) it is as ID 15 so the second unit would receive the data. All the modbus registers and coils should be identical. When the secondary responds and transmits data the PI would again strip the ID 15 header and spoof it with ID 14 and forward. The system (in my case a Huawei Sun2000 inverter) should then see both batteries .

The combiner unit that LG no longer sell is simply a junction box that loops the DC power and the Modbus connections although it does include 60A DC fuses on each DC leg (SEG1 - SEG2 - Inverter) so 6 fuses in all - no electronics in the box at all, so it's diy doable. Any thoughts?

TiA
Roy

[warx]

I finally sourced (with help) a real-bonafide SEG2 after 2-1/2 years last month. So luckily my problems are solved. It looks significantly different although part of the deal was getting my new solar company (my old went out of business) to install and continue the warranty so I did not get the closest look. I do not have a combiner however. The replacement SEG2 had to be re-wired differently from the "second" SEG1.