I have been pondering the question of peak power from my inverter for a while and read this very useful thread.
https://community.victronenergy.com/questions/4454/peak-power-of-victron-inverters.html
As per the question title I have a Multiplus 12 1200 50 installed in my boat (bought to replace an 1100va industrial non-sine wave inverter installed for the previous owner). It is connected to a Victron 165Ah Gel battery (with the intention to add another of the same size)
Under normal circumstances this is perfect.
In the galley we have a 1500W kettle which we only run when hooked-up to shore power.
In the quoted thread the half-hour rating is worked back from AC power and in my case is 5A.
Also in the quoted thread it says that 130% of the nominal AC power can be supported for 30mins if the voltages remain stable this equates to 1560W or 6.5A.
Yesterday a visitor accidentally conducted an interesting experiment by boiling the kettle with the boat moving (no shore power).
VRM shows that for the 3 mins it took to boil the kettle the inverter drew ~150A from the battery. This brought the SOC down to 85% and generated VE Bus Overload L1 and Temperature L1 warnings (not alarms).
Question 1: Can VRM be queried to find the values for these warnings?
Question 2: The Multiplus manual says that 150 -700Ah of battery capacity is appropriate. Assuming the maximum discharge current is 0.2C that equates to 30-140A max discharge and so if I wanted to run the kettle via the inverter I need 700+Ah of battery?
Question 3: The battery datasheet says that the 5 min rating is 24% or ~40A with the 5s current 7C or ~1100A .... will pulling 150A for 3 mins harm the battery? I guess so if done repeatedly?