I’m curious what the use case would be to have a fridge plugged into AC and DC at the same time. It seems like a bad idea.
Since many new vehicles include a small inverter, the use case is simple to understand. When plugged into the vehicle's factory AC inverter, and the 12V system, the fridge will be powered by the AC when the vehicle is running. Battery power will be used when the vehicle is stopped. This is the intended design. They just screwed it up...either internally (within their engineering group) or by allowing a third party to handle some design details which is extrememly common in Asian production arrangements.


