My P20 was - prior to some changes - feeding BHK 300’s; BHK Pre; DS DAC and Transport for years trouble free.
Then, after 4 months in storage during a lounge do-over, I reconnected - but also added a Samsung 85 inch Neo QLED TV; SONOS Playbar; small network switch and HiFi Rose B150.
Ran fine overnight, but the next morning my dedicated DB breaker tripped. My system is isolated from the grid by 22.4Kwh Lithium Ion batteries and a Victron inverter. I re-set the breaker but it tripped again later on, twice. Note that my full system was in standby mode during the latter x2 trip episodes with perhaps only the SONOS not in standby.
Then I just happened to notice that I’m drawing 1200 watts from my inverter, where it should be around 800. On a whim I felt the P20’s heatsink fins, and sure enough they were hot as hell. With system in standby mode??
Disconnected TV, SONOS, Rose and switch from the P20, plus a firmware upgrade from shipped-with to 1.25. It’s now been 2 days and all is fine.
In summary then: It seems as though the P20 was “acting” as though it was operating at (say) 80% or more capacity, as proven by the excessive heat, and drawing way more power that it should’ve - while my system was in standby. Causing the breaker to trip.
I do not think it’s inverter related because it’s not the inverter that tripped. It is of course possible that a high draw from the P20 caused the tripping, and therefore I also had the 10A changed to a 20A breaker. But what caused the excessive draw from the P20, causing all that heat?
Below from PSA back in 2011: (I do not know if it may be relevant here). Switching supplies (including the GC series amplifiers) usually have a large capacitor right across the power line. The old style Power Plants (P500/P1000 and earlier) had a very difficult time with capacitive loads. This is because a capacitor draws the most current when the voltage is lowest. The old Power Plants had fixed power supply rails, and this means when the output voltage is 0, all of the voltage is across the power transistor. So the capacitor draws the most current at the moment the voltage across the transistor is also its maximum, This meant a lot of heat inside the Power Plant.
The newer Power Plants (starting with the Premier) have variable rails that follow the AC power. In this design the voltage across the transistor is about the same all the time. This design is not sensitive to when the current is being drawn, so capacitive loads do not affect it that way.
Still, capacitive loads have a low power factor. This means that they have a relatively high current (amps) for the amount of power (watts) they use. Ultimately it is the current that is the limiting factor for the Power Plants. Unfortunately most users only understand watts. The P5 and P10 display the power being used in watts, but the percentage is calculated from the current (and the voltage).
To make a long story short: Yes, I believe the display percentage can be trusted. However the downside is there are occasionally questions like “Why does my unit say 75% when the load is only 500 watts? It’s a difficult question to answer. The Power Plant is calculating the percentage based on the things that really matter inside the unit.
I suppose it is also possible that something in the load (even extremely low as it was) presented to the P20, caused it to behave as though it’s somehow sensing a much bigger load. And maybe 1.25 fixed this; and I could now happily connect the SONOS, Rose, Switch and TV up again??