question

johnt avatar image
johnt asked

ESS 0%minSOC Multiplus II Best way to hold off inverter/feedin restart until battery SOC reached?

I have an ESS system with the following parts:

  • 1 Multiplus II per 3 phases
  • 1 Redflow 10kWh Zcell (wants regular full discharge ... 0% minSOC)
  • 2 Victron MPPT
  • 1 CCGX
  • Grid meter
  • Australian grid
  • Don't want to charge battery from grid

We are finding some mornings after first light,
all Multiplus will switch off for around 10 seconds to 10 minutes.
Particularly if a large load was running (water pump).

I am guessing this is occurring when the Multiplus II are trying to hold all load on inverter as part of enabling feedin?

From my VRM data, it looks like this happens when:

MPPT voltage goes high
Battery SOC 0%
Battery dischage limit 0A

I would like to be able to set an ESS inverter restart minimum battery State of Charge, or for ESS not to enable inverter until a battery discharge limit is reached?

To work around this in the short term, I could run something on the ccgx:

  1. Once the battery hits minimum SOC, the inverters are held off until a SOC is reached, through either:
  2. Once this desired restartSOC is reached, revert the setting


Which would be the better approach? Or any other suggestions?



VRM Installation ID is 33453
A recorded example: 2019-05-29 06:42 local time

Cheers,

John

ESS
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

1 Answer
Paul B avatar image
Paul B answered ·

I suspect that you are flatneing the batteries and the voltage is getting to low when you are going down to 0 SOC and the battery or the inverter is then turning off or turning off suppling power to all loads.


So look at your batty voltages and inverter min voltage settings

also

why not set the SOC to say 5 or 10% that one would think would be close enough and the grid set point to say 100w then the multi will draw power from the grid once the battery reaches say 10% SOC and the SOC wont go any lower,

or

Set the grid setpoint to 100w and min SOC to 1% the system will draw 100w from the mains and the rest out of the battery until 1% SOC is reached then it will draw all power from the grid,

the below are ny settings change the 85 to 1% or zero and see how you go


1559799315936.png (39.2 KiB)
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.