Good morning, I purchased the Multiplus 12/500/20 with the aim of creating a home UPS for my PC and network equipment. I paired it with a 12.8V 100Ah LiFePO battery. I would like to have some advice on the configuration and some clarifications. I noticed that the recommended settings from the battery manufacturer regarding charging (manual here: https://cdn.shopify.com/s/files/1/0561/7641/0714/files/Redodo_12V_100ah_lithium_battery_Product_Manual.pdf) coincide with the default settings of the inverter, so I don’t needed to change inverter settings. Please correct if I’m wrong! I connected the inverter to the battery, and after a short charging period (the battery was probably already almost fully charged), the inverter switches to inverter mode, so the “charger” charging LED turns off and the green “inverter” LED turns on. What puzzles me is that, even in the absence of a connected load, the inverter after a short period of time in “inverter” mode (about 10-15 seconds) switches back to “charger” mode, stays like that for about the same time (10-15 seconds), and then switches back to “inverter”… and so on, endlessly! I would like to know if this is normal behavior and if there is a way to prevent these continuous relay switches. To clarify, under normal conditions, when there is grid power, I would prefer the inverter to remain inactive (unless it is necessary to charge the battery) and the load to be powered by the grid; the inverter should activate when the grid power goes out and deactivate again (and switch to battery charging mode) when the power returns. Is it possible to operate the Multiplus in this way? How can I configure it correctly? If I set the inverter to CHR mode, it stays off for 10-15 seconds and then switches to charging mode, but after about twenty seconds, it disconnects and the red alarm LED flashes for about 30 seconds, then it switches back to charging mode… Is this all normal? If not, how can I fix it? Thank you in advance for your help.

[image] fabrixpo: after a short charging period (the battery was probably already almost fully charged), the inverter switches to inverter mode, so the “charger” charging LED turns off and the green “inverter” LED turns on. What puzzles me is that, even in the absence of a connected load, the inverter after a short period of time in “inverter” mode (about 10-15 seconds) switches back to “charger” mode, stays like that for about the same time (10-15 seconds), and then switches back to “inverter”… and so on, endlessly! I would like to know if this is normal behavior No this is not normal. You need to check the inverter SOC value and settings, also the ignore ac in setting. The inverter should also be configured for UPS mode, as this is what you are using it for. Battery charging and switching should be done on battery voltage,and not SOC. Depends on the rest of your inverter settings. In normal operation, the inverter’s charger should start in bulk, go to absorption, and then go to float. Do also check to see that your battery is properly connected, and can drive the inverter before you connect the AC in.

For anyone still reading this. The default DIP Switch settings for LiFePo4 batteries are usually not correct. The default Lithium battery Preset values (in the VE Config application) also do not fit typical cases. I am going through the setting up of a similar system. Read the required steps here: [image] Inverter briefly switches off after battery is fully charged DIY Hi all. I just received some older hardware, that was sitting in the storage somewhere for approx. 5 years. Inverter MultiPlus - 1600VA (48 Vdc) Battery Dyness B4850 (LiFePo4, 2.4 kWh) with CAN bus connection Display CCGX (Color Control GX - seems to be a bit older, limited documentation exists) [image] After a full day of wiring, configuring and figuring out correct pinouts for a CAN bus, got the system working. CCGX was updated to the latest version. Can’t update the inverter as I don’t h…

Multiplus 12/500/20 and redodo LiFePO battery for home PC UPS

DIY

Aly (Aljaz) 16 May 2026 19:16 3

For anyone still reading this.

The default DIP Switch settings for LiFePo4 batteries are usually not correct.

The default Lithium battery Preset values (in the VE Config application) also do not fit typical cases.

I am going through the setting up of a similar system. Read the required steps here:

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Multiplus 12/500/20 and redodo LiFePO battery for home PC UPS

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