On the road with new inverter and residential fridge. When driving with the inverter on (for the fridge), the chassis battery volts drops slowly to 12.3V. Fearing the worst, I ran the generator to charge both banks. Once at the campground for the night, I read the Beaver book. It said the BIRD will open at 12.0v to recharge the chassis batteries via the alternator. My build sheet says I have a 160a alternator. I expected that, when driving, the alternator would to 'cover' both the chassis load (engine running) and house (30a dc draw) while running the fridge. Am I expecting too much from the alternator? Tomorrow, when we head north, I will see if the chassis batt volts drops below 12.0v and then if BIRD opens, charging the chassis battery. Plan to stop by an alternator shop in Eugene to have them check its output.