Standards like the National Electrical Code (NEC) mandate that the panel's interior be protected from accidental contact and foreign objects. The door also conceals the breaker box, allowing it to. However, the key to a safe and reliable system lies in proper installation. If it's done poorly, you risk short circuits, fire hazards, or system failure. In this guide, we'll break down everything you need to know to install. This 30-inch width does not need to be centered on the panel, but it must allow the panel door to open a full 90 degrees to ensure complete accessibility to the breakers inside.