Wire size depends on three main factors: current load (amps), circuit distance, and voltage drop requirements. Always size wire to handle 125% of the continuous load. This technical article covers recommendations for choosing cross-sections of the wiring conductors inside switchboards, their connection methods, various wiring dos, don'ts and precautions in protecting from short-circuit and magnetic effect. Calculate proper wire gauge, voltage drop, and ampacity for safe electrical installations. Input your electrical parameters to get accurate wire size. It is essential for an initial installation that the designer selects trunking and conduit systems that are sized correctly so they can comfortably accommodate the number of circuit conductors required. A junction box protects wire connections from physical damage, reduces shock and fire risks.