ok, we know that the maximum number of circuits for a panel is 42.
Let's say i have a 100 Amp panel and have used all the circuits but still have capacity. Can I buy a panel with main lugs only and connect the busbars to the existing 100 Amp panel provided that the new panel is also 100Amp rated?
Wires connecting the bus bars will be of adequate size like a #3. Thanks.