[Bug?] Erratic DESS charging / missing Target SOC after updating to Venus OS v3.70

by Van Rhys · 3 hours ago 11 views 1 replies
Van Rhys
Van Rhys
Member
2 posts
thumb_up 1 likes
Joined Sep 2024
3 hours ago
#3806

Right, so I've been seeing something proper odd with my setup since pushing the v3.70 update through to my Cerbo GX last week. Got a Victron LiFePO4 pack feeding into DESS, and it's completely lost the plot with target SOC behaviour.

What's happening: The charge controller will start pulling power, hit what should be my target SOC (say, 80%), then just... doesn't stop? Voltage climbs way past where it ought to. Then it'll drop off erratically and try again. Meanwhile the "Current Target SOC" field in the GX display is either blank or showing something that doesn't match my schedule at all.

I've triple-checked the DESS configuration — matrix is tidy, generator set logic looks sound, target SOCs are clearly defined in the schedule. But something in the firmware update seems to have borked the handshake between the ESS assistant and whatever's polling the target value.

Has anyone else experienced this since v3.70? I'm wondering if it's:

  • A known issue with DESS specifically
  • Something about how the update handled existing schedules (mine was created under v3.62)
  • Related to the Victron/BMS comms layer

I haven't rolled back yet because I want to gather some data first, but I'm also not keen on hammering my battery with erratic charging cycles. Keen to hear if others are hitting this or if I've just managed to corrupt something in my config somehow.

What diagnostics should I be pulling to help troubleshoot this?

Liam Clark
Liam Clark
Member
1 posts
Joined Jun 2025

@VanRhys - Have you checked if the Target SOC setting migrated properly during the update? I've seen this crop up before with Venus OS point releases - sometimes the configuration files don't carry over cleanly, especially with DESS settings.

Worth having a look at Settings > System Setup > Battery Monitor to verify your LiFePO4 is still being detected correctly. Also check the DESS config under Settings > DVCC - occasionally the Target SOC field goes blank after updates.

If it's still missing, try a manual reboot of the Cerbo via the GUI rather than just a power cycle. That usually forces a proper settings reload. Let us know what you find and we can dig deeper if needed.

Log in to join the discussion.

Log In to Reply