2000w Inverter Install

Anytime the car is Ready, the 12V battery is in good shape, regardless of EV/Hybrid/Charge mode setting, unless you're actually drawing too high a load from it with the inverter. I suppose that monitoring 12V voltage is a good idea if you're going to be pulling a lot of power continuously from the 12V, Ready or not. For a few minutes, the 12V battery should be strong enough to buffer a high demand. I did buy a couple of cheapo 12V battery monitor/alarm devices to display the voltage and beep if low, but I haven't used them yet. The voltage can be watched with an OBDII dongle and free phone app like Torque Lite. Not sure if it has an alarm function, but can definitely be used as a gauge.

I don't think I'll personally ever need to draw more than 30A from the Prime 12V, and will likely DIP-switch select 20A going through my DC-DC converter. So I'm pretty unconcerned about it affecting the car adversely while the car is Ready, or even for an hour or so with the car off The 12V monitor/alarm should only come into play if I pull power from the 12V with the car off.

My own 2000W inverter will run off my LiFePO4 battery rather than the car battery, and I'll only rarely pull 700W from that, usually under 100W.

Note that I do carry a good 12V jump pack with 160psi air compressor built into it (Uibi X7). And that because I'm using my DC-DC to charge a 100Ah LiFePO4 battery, I can always use the LiFePO4 to power a battery charger to the car 12V if I somehow drain it.