The answer to 'why is my generator circuit overload' is that the generator is being overloaded by drawing too much electrical current. This can happen if you have too many high-wattage appliances or devices running at the same time, or if there is a short circuit or other electrical fault in the system.
Some common symptoms of a generator circuit overload include the generator shutting off, circuit breakers tripping, or the generator making strange noises. To fix the issue, you'll need to reduce the electrical load on the generator by turning off some devices, checking for any short circuits, and making sure the generator is properly sized for your power needs.