When my Multiplus 2 5000 GX is idle, my battery is drained with 2,2 amps about 116 watt, which depletes my 314Ah 48 volt battery with 7 percent (around 1,2kWh) each 12 hours.
I checked the current with a multimeter which also shows around 2,2 amps until a spike blowed the internal fuse of the multimeter
The victron in float mode only uses 20 to 30 watts.
Why is the victron using more than 100 watts in idle mode?
It seems also that in idle mode the victron tries to match the grid with the load while in float mode the loads are around 20 watts lower than the grid measurement which shows a self usage of approximately 24 watts.
Btw: In the picture of float mode my switch at the bottom of the Multiplus was accidentally on position 2, charger only.
When I disconnect mains and load, the power usage of the multiplus drops to 15 watts while the inverter is still active which is according to the specifications. So grid connection is causing a loss of approximately 100 watts.
What happens, when you drop the loads, but leave the mains connected?
I also have around 100 Watts idle usage, but after all that doesn’t really make a difference. What leaves the battery is consumed, so it’s not like you are loosing energy in a sence - it minimizes the amount beeing pulled from grid by that amount. It doesn’t just magically vanish.
The only thing that I can imagine that it is lost in the victron as heat. It actually keeps quite cool, but 100 watts over a metal case doesn’t probably heat up very much.
This is at a friend of my, his multiplusses 2 5kW 48v are drawing 0,3 amps each from the battery while the inverters are connected to the grid, which is indeed the specified 16 watts of idle usage.
I think my unit has a defect in the ac synchronization.
I contacted the dealer and he said to wait until after the holidays to get more responses on this topic, hopefully from Victron.
Dess has sold all the energy until soc limit. Now the inverter uses 22 watt in charge mode. I think the 120 watt power usage will return as soon as the multiplus returns to discharging state again.
The problem is that the victron has a loss of 120 watt in discharge mode.
In float, bulk or invert mode the loss is about 20 watts.
Is this a hardware fault or normal power loss when in discharge mode?
And when it’s normal behavior can the dess code be changed that when the system is not charging or discharging it stays in bulk mode without charging so the power loss is minimized to 20 watts instead of 120 watts?
Still my discharge loss is pretty high, in the graphs from Multiplus-II 48/5000 efficiency curve - VictronEnergy I see that the efficiency is 96% at 1000 watt discharge which is a powerloss of 40 watts and at 95% at 500 watt discharge which is a power loss of 25 watts, a lot less than the powerloss of 120 watt my MP2 has. So I still think there is something wrong in the MP2.
It’s set to 0 watt, but in DESS trading mode this value is not used (yet). Also the 100 watt disappears, it’s not deducted from the total load, nor it’s feed back into the grid.
At a friend of mine who has a 3 fase system his discharge current in DESS idle is only 1,1 amps, so 0,36 amps per Multiplus 2 which is just 19 watts per unit (where my unit consumes 120 watts).
So I think my unit is defective. Hopefully @guystewart can still help to see if my unit needs to be swapped or repaired under warranty (I received it 12 days ago).
In this picture the battery voltage and current shows that after charging in discharge mode (while dess has a soc setpoint of 100%), the battery discharges from 54,4 at 12:00 to 53,6 volts at 16:00, measured by the victron while the victron also says 0 amps (and the bms shows the real 2,2 amps). This picture confirms again that the battery measured current is correct and the victron measured dc current is incorrect and there is a loss of approximately 120 watts during dess idle (soc = target soc) in discharge mode.
I bought an dc current clamp meter on Amazon to check currents, I don’t trust the jkbms current. When I calculate according to voltage drop the result is a 40watt drain. Still to much, but when the victron in dess mode would stay in charge mode instead of discharge, the energy loss will be limited.
