White box next to the distribution box

A white box next to a distribution box is often a sub-distribution board, control box, or junction box used to manage additional circuits, control devices, or safety components.Possible FunctionsSub-Distribution Board: In many residential or commercial setups, a secondary or sub-distribution board is installed next to the main distribution box to handle additional circuits, such as for a garage, electric vehicle charging station, or smart home modules. It allows for easier expansion without overloading the main panel and ensures proper circuit protection and organization . Control Box: A control box is designed to manage and regulate electrical devices rather than just distribute power. It may contain switches, relays, timers, or programmable logic controllers (PLCs) to automate or control specific equipment, such as pumps, motors, or lighting systems . Junction Box: Sometimes, a white box serves as a junction box, which is primarily used to connect and protect wiring from the main distribution box to various circuits. It provides a safe enclosure for splicing wires and can be used indoors or outdoors depending on its IP rating .Identification TipsLabeling: Check for labels or markings on the box. Sub-distribution boards often indicate circuit numbers or RCDs, while control boxes may list equipment or automation functions.Internal Components: If safe to inspect, a sub-distribution board will contain miniature circuit breakers (MCBs) or residual current devices (RCDs). A control box will have relays, contactors, or timers. A junction box usually contains only wire connections.Connection to Main Box: Observe how the box is wired. A sub-distribution board is typically fed from the main distribution box, while a control box may have separate inputs for specific devices.Safety ConsiderationsAny box adjacent to a distribution box should be installed according to electrical codes and standards, such as DIN VDE 0100 in Germany or local regulations elsewhere. Only qualified personnel should modify or inspect these boxes to prevent electrical hazards . In summary, a white box next to a distribution box is usually an auxiliary electrical enclosure—either a sub-distribution board, control box, or junction box—serving to expand, control, or safely manage circuits beyond the main distribution panel .