# Modbus Multi RS ESS minimum SoC setting address? **URL:** \ **Category:** Modifications\ **Tags:** modbus\_tcp, cerbo\_gx, ess, multi\_rs\ **Created:** [20 March 2026 15:14 UTC](https://community.victronenergy.com/t/modbus-multi-rs-ess-minimum-soc-setting-address/55216 "2026-03-20T15:14:19Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Thieu](https://avatars.discourse-cdn.com/v4/letter/t/a698b9/32.png) [@Thieu](https://community.victronenergy.com/u/Thieu)\ **Post date:** [20 March 2026 15:14 UTC](https://community.victronenergy.com/t/modbus-multi-rs-ess-minimum-soc-setting-address/55216/1 "2026-03-20T15:14:19Z")
I’m trying to read and control ESS Minimum SoC over Modbus. The address is 2901 on ID100. This is for the Cerbo, I can change the value over Modbus, and the value readout over Modbus is changed accordingly, but it does not affect the running ESS. The ESS in a Multi RS setup is managed by the Multi RS, not the Cerbo, but I can’t find any address for this setting in this setup. Not available jet? (2903 is more important to me, but for troubleshooting is 2901 more convenient…) ---
**Author:** ![evgeniy.labunskiy](https://dub1.discourse-cdn.com/victron/user_avatar/community.victronenergy.com/evgeniy.labunskiy/32/114_2.png) [@evgeniy.labunskiy](https://community.victronenergy.com/u/evgeniy.labunskiy)\ **Post date:** [20 March 2026 15:40 UTC](https://community.victronenergy.com/t/modbus-multi-rs-ess-minimum-soc-setting-address/55216/2 "2026-03-20T15:40:52Z")
I think ID100 is generic system. But you need com.victronenergy.multi ---
**Author:** ![Thieu](https://avatars.discourse-cdn.com/v4/letter/t/a698b9/32.png) [@Thieu](https://community.victronenergy.com/u/Thieu)\ **Post date:** [20 March 2026 17:24 UTC](https://community.victronenergy.com/t/modbus-multi-rs-ess-minimum-soc-setting-address/55216/3 "2026-03-20T17:24:16Z")
Thank you! That works indeed! I hadn’t read through the register list sufficiently. The value comparable to 2903, which I need, is com.victronenergy.acsystem address 4925.