This is a 12 k all in one inverter. It is low frequency split phase inviter with two mppt charge controllers. The only time the graph from the Victron shunt looks like this is was the Battery are getting topped off wile a load is on the inverter. If there is no load, smooth output of the chargers. If there is load and the battery voltage is down to lets say 48 volts, smooth output. If there is Load on the inviter and the voltage is like 54 56 volts, then the output is not smooth, I have seen the Victron shunt gong from 1500 watts in and 1500 out of the battery's (like the graphs shows) This does not reflect the load on the Inviter. (smooth even load on the Inviter.) If I shut off solar power to one of my built in charge controls at a time, does not stop this from happening. Both built in charge controllers do the same thing independently. if one is disconnected.