电缆芯线截面的选择还应符合下列要求：
The selection of cable core section shall also meet the following requirements:
（1）电流回路：应使电流互感器的工作准确等级，此时，如无可靠根据，可按断路器的电流容量确定最大短路电流。
(1) current circuit: the working accuracy level of current transformer shall be ensured. At this time, if there is no reliable basis, the maximum short-circuit current can be determined according to the current capacity of the circuit breaker.
（2）电压回路：当全部保护装置和安全自动装置动作时（考虑到发展，电压互感器的负荷最大时），电压互感器至保护和自动装置屏的电缆压降假山制作 不锈钢铸件 铝箔真空袋 七孔梅花管 hdpe硅芯管 液压钢坝 PVC软管 飞行激光打标机 沥青保温泵不应超过额定电压的3%。
(2) voltage circuit: when all protective devices and automatic safety devices act (considering the development, the maximum load of voltage transformer), the cable voltage drop from the voltage transformer to the protection and automatic device panel shall not exceed 3% of the rated voltage.
（3）操作回路：在最大负荷下，操作母线至设备的电压降，不应超过10%额定电压。
(3) operation circuit: under the maximum load, the voltage drop from the operation bus to the equipment shall not exceed 10% of the rated voltage