The answer to 'why is my junction box power surge' is that a power surge in your junction box is usually caused by an electrical fault or sudden increase in power demand. This can be due to issues like faulty wiring, overloaded circuits, or a problem with your home's electrical system. Symptoms may include flickering lights, tripped circuit breakers, or damage to appliances.
To troubleshoot, start by checking for any loose or damaged wiring in the junction box. Make sure the box is properly grounded and all connections are secure. You may also need to inspect your circuit breakers and consider upgrading your electrical panel if it's outdated or not handling the power demands of your home. If the issue persists, it's best to call in a licensed electrician to diagnose and fix the problem safely.