I routinely untick "Enable battery monitor" because the batteries we use always have an internal BMS which provides SoC et al.
I noted today during a commissioning that the size (Ah) of the battery in the ESS configuration is tied to whether the battery monitor is enabled or not on the General tab.
With "Enable battery monitor" ticked:
With "Enable battery monitor" unticked (note also the two mentions of battery capacity differ 10Ah vs 0Ah):
It shouldn't make any difference if the internal one is On, the BMS manages the battery. Just set your ESS to the correct AH capacity and leave it like that. Because the BMS is selected as the battery monitor the internal one is of no consequence as SOC comes from the BMS.
What I’m trying to say is there is no use setting the ESS SOC, because it gets lost if you untick enable battery monitor
Hi @warwick
this has a reason and is also stated in the manual:
https://www.victronenergy.com/media/pg/Energy_Storage_System/en/configuration.html#UUID-7435bdda-8f3f-81c2-a1a6-dc8f1c9b2f8f
[quote]
General tab: the ESS Assistant will have enabled the built-battery monitor. Leave that enabled (!). Also when there is a BMV or intelligent canbus-connected battery in the system.
Crap. We need to amend some battery documentation eg. FreedomWon to reflect this. @Guy Stewart (Victron Community Manager), remember this during the FW documentation process - we said it didn't seem to matter whether on or off.
Indeed,
Apologies for the confusion there, my advice was to leave the option and not mention it. It is automatically enabled.
I was specifically thinking of the selection of either the BMS or MultiPlus battery monitor in the GX device as the primary State of Charge that is shown - this is always prioritised by default to the BMS (over the built in monitor). That does not need to be adjusted.
I did not consider that other component when I said that it happened automatically. But it the SIZING of the battery does indeed matter so it should be mentioned, and explained how to calculate the Ah based on the number of modules.
