Wiring of 2 circuit breakers in the distribution box

To wire circuit breakers across two distribution boxes, connect the main feed to the first box, then use a properly rated feeder cable to supply the second box, ensuring correct breaker sizing, neutral and ground connections, and load balancing.Step 1: Plan and Assess LoadBefore wiring, calculate the total electrical load for each distribution box. Group circuits by type (resistive, inductive, capacitive) and apply safety margins, typically using 80% of the rated current for continuous loads . This ensures breakers are correctly sized and prevents overloads.Step 2: Main Feed to First Distribution BoxConnect the incoming utility feed to the main breaker of the first distribution box .Install an RCD or GFCI if required for ground fault protection .Connect the hot wires to the busbars, neutral wires to the neutral bar, and ground wires to the grounding bar .Step 3: Feeder to Second Distribution BoxUse a properly rated feeder cable (size depends on load and distance) from a breaker in the first box to the main breaker of the second box .The second box acts as a sub-panel. Its neutral and ground bars should be separate to prevent neutral-ground bonding issues .Connect the feeder's hot wires to the second box's main breaker, neutral to the neutral bar, and ground to the grounding bar.Step 4: Install Branch Circuit BreakersSlide each branch breaker onto the busbar until it clicks securely .Connect hot wires from each circuit to the breaker terminal, neutral wires to the neutral bar, and ground wires to the grounding bar .Ensure each breaker matches the wire gauge and load (e.g., 15A breaker for 14-gauge wire, 20A for 12-gauge wire), .Step 5: Safety and TestingVerify all connections are tight and properly insulated.Ensure load balancing across phases if using a multi-phase system .Turn on the main breaker and test each branch circuit for correct operation.Follow NEC or IEC codes for spacing, breaker types, and protective devices .Key ConsiderationsLeave extra space in each box for future expansion .Use comb busbars for safer and cleaner connections .Always turn off the main isolator before working inside the panels .If unsure, consult a licensed electrician to ensure compliance and safety. By following these steps, you can safely wire two distribution boxes, maintain proper load distribution, and ensure protection against overloads and faults.