In the last 24 hours whilst away from the boat the lithium batteries has dropped from 90% down to 74% so 16% used.The usage has been 2.7kw and the battery bank is 30kw total. It appears the maths show the 16% drop is 4.7 KW so the question is does the inverter use 2kw of battery power for itself over the 24 hours
Is it on? Off? In AES? Definitely with no load? What size quattro?
Are you sure the SOC is correct? Where does it get the information from?
When you say "the usage has been 2.7kW" what do you mean? Which Quattro do you have? What else is taking power when you're away from the boat?
I have a Quattro 48/10000 with all the usual other bits like Cerbo/Touch50, MPPT controllers, DC chargers, internet router, CH controller and so on. Average power use over the last week has been 2.4kWh/day which is exactly 100W average, pretty much as expected given the Quattro is specced at 60W idle power and various other things take a few watts each.
BTW this is when plugged into shoreline; I found that when the Quattro was set to inverter only most of the time so the SoC dropped (turning it back to charge every few days to get back up to 100% SoC) this made better use of power from the solar panels, but the actual consumption from shoreline was about 20% higher on average than leaving it in auto mode -- presumably due to losses while charging.
Quattro 48/8000. The boat is electric with domestic fridge freezer, electric cooking, starlink broadband,, 1.5kw solar and 6 x 5kw lithium @ 48 volts. When away from the boat the fridge freezer is on along with starlink and battery charged for the on board generator and bow thruster. All other appliances are off.
The victron controller showed a kw usage of 2.7kw over the 24 hour period but the % of battery drop is 16% over the same period. The battery started off at 90% full. The remote console shows the battery state at 100%
How much do you trust the SoC level -- where does it come from and how is it sensed? (BMS, voltage and/or current shunt...).
How is the output power split between DC and AC loads? Are you including both in your measurements?
If you've really got 2kWh/day "missing" that's an average of 83W which only seems a tiny bit high -- the Quattro 48/8000 is specified at 60W zero-load, the same as my 48/10000. There have been reports of some Quattros taking rather more standby power than specified, the only way to check this is to disconnect absolutely everything that draws any power and see what remains.
Don't forget things that might only take a few watts (e.g. Cerbo if you have one), you're not looking for a very big discrepancy here.
