Switchis a critical component of power supply and distribution systems, acting as an intermediate station for delivering electrical energy to end-users. Within electrical power system distribution equipment, distribution panels (also called switchgear) are used for power generation, transmission, control, and protection, maintaining normal grid operation. During faults, it promptly disconnects the affected section, and during electrical maintenance, it isolates live Utrustning . Distributionspaneler används i stor utsträckning, ansvariga för energigivande och urinriktning av normala kretsar, samt rensning av felaktiga linjer . De är oumbärlig utrustning inom kraftsystem, spelar en viktig roll för att kontrollera och skydda de säkra och stabila driften av det nationella rutan och dess belastning .}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
The arrangement of distribution equipment and the selection of conductors and electrical apparatus shall satisfy the requirements for normal operation, maintenance, short-circuit, and overload conditions, and shall not endanger personnel safety or surrounding equipment. The insulation level of the distribution equipment shall be coordinated with the rated voltage of the power system. When adjacent live parts within the distribution equipment have different rated voltages, the safe clearance shall be determined Baserat på den högre nominella spänningen .
When selecting conductors and apparatus, the relative humidity used shall generally be the average relative humidity of the month with the highest local humidity. The maximum permissible working voltage of the selected conductors and apparatus shall not be lower than the maximum operating voltage of the respective circuit. Their long-term permissible current shall not be less than the maximum continuous operating current of the circuit. Additionally, their dynamic stability and thermal stability shall be verified under short-circuit conditions. Conductors and apparatus protected by fuses may be exempt from thermal stability verification but dynamic stability verification is still required. For conductors and apparatus protected by high-voltage current-limiting fuses, dynamic and thermal stability verification can be utförs baserat på egenskaperna hos den nuvarande begränsande säkringen . för spänningstransformatorkretsar skyddade av säkringar, verifiering av både dynamisk och termisk stabilitet kan utelämnas .}
When determining the short-circuit current, the calculation shall be based on the normal system configuration likely to produce the maximum short-circuit current, taking into account the power system's 5–10 year development plan and the project's own plan. When calculating the short-circuit point, the location where the short-circuit current is the highest under normal system configuration shall be selected. For 6kV or 10kV outgoing feeders equipped with reaktorer, ledningar och bussningar belägnaföreBarriären (på reaktorns linjesida) ska beräknas förutsatt att kortslutningspunkten äruppströmsav reaktorn . leder och apparater belägnaefterBarriären (på reaktorns belastningssida) beräknas i allmänhet förutsatt att kortslutningspunkten ärnedströmsav reaktorn .