[DutchmenSport]

If all you did was cut power from the cut off switch, you still have other items using your battery and they are not powered off. Co2 detector is one of them. It is not wired through your battery cut off switch.

Smoke detectors will also chirp when their batteries get low.

Also, if your house battery is low, the converter (that panel with all the breaker switches and the automotive style fuses) will also make a beeping sound ever few minutes. It's a warning your house battery is low.

Simply flipping that switch will not turn everything off. If you truly want everything turned off, disconnect the battery. The easiest way to do that is to simply remove the ground (black) wire from the battery.

If you have a residential refrigerator, there is yet another cut-off switch that runs to your inverter. Of course if the inverter is turned off, it won't draw down the battery. But if it's turned on, it will draw down the house battery, regardless if the other cut-off is on or off.

Disconnect the battery cable at the battery. This is the only true way to kill everything using your battery.