When do I need a dedicated circuit for plug-in solar?

You need a dedicated circuit once your plug-in solar goes beyond roughly 400W.

For why a single kit tops out at 360W in the first place, see our guide: Why our plug-in solar kits max out at 360W.

Why doesn't the breaker just protect me?

Because it may not "see" the current. A breaker trips on current flowing through it from the panel. Solar feeding in downstream adds current to the circuit's wiring without passing through the breaker, so as systems get larger the breaker stops being a reliable backstop. That is the reason for the size threshold, rather than any concern about the kit itself.

Can I run two kits from the same outlet?

Not from the same outlet. Two kits can share one dedicated circuit if the total stays inside the continuous limit, but running them from a general-purpose circuit that also serves appliances is where you run out of margin.

What if my home has old wiring?

Have an electrician check the circuit first. Code margins assume real-world imperfections such as kinked runs, limited airflow in conduit and terminations that are good rather than perfect. When in doubt, it is always worth confirming rather than assuming.

Does a dedicated circuit need anything special?

It needs to be a circuit that serves only your solar. Standard 14 AWG wiring on a 15-amp breaker covers most plug-in setups comfortably. Outdoors, it still needs GFCI protection, the same as any outdoor receptacle.

How do I know what else is on my circuit?

Switch the breaker off and see what loses power. It is worth doing before you add anything, because circuit layouts in older homes are often not what you would expect.

This question set off one of the most detailed technical debates the Bright Saver Community has had, with several people bringing real electrical experience and working through the numbers.