The switch configuration of lw3-12 / 630-20 outdoor pole mounted circuit breaker fully meets the requirements of primary and secondary integration of State Grid, which is convenient for unified procurement and mass production of State Grid. The switch has compact structure, reasonable layout and complete functions, and all indicators meet the requirements of primary and secondary integration of State Grid; The protection CT, zero sequence CT and zero sequence voltage sensor with unified parameters have the characteristics of wide measurement range, high measurement accuracy and high reliability. The analog quantity is complete and it is easy to accurately determine various faults of the line.
The material of circuit breaker box is 3mm304 stainless steel, and the protection grade is not lower than IP67; The shell is provided with an obvious opening and closing position indicator which is easy to observe on the ground. The indicator is reliably connected with the operating mechanism, and the indication action is reliable. 12mm diameter antirust grounding screw shall be used, and the grounding point shall be marked with grounding symbol. The surface of the shell is convex and will not store water for a long time. The shell is equipped with handling handle to avoid pulling the outlet sleeve. Equipped with lifting rings, the switchgear in suspension can be kept level, and there is no friction contact between the chain and any parts, so as to avoid scratching the surface coating of the box during hoisting. The name plate is made of 304 stainless steel, which is weather-resistant, corrosion-resistant and can be clearly seen during use. The content of the name plate meets the requirements of relevant national standards.
Circuit breaker configuration:
Three phase current transformer + zero sequence current transformer are provided; Transformation ratio of current transformer: phase current 600 / 1; The zero sequence current is 20 / 1. Accuracy level: primary phase current: measurement accuracy level is 0.5, protection 5p10; When the input current of zero sequence primary side is 1A ~ rated current, the error is less than or equal to 3%, and when the primary current is 100A, the error is less than or equal to 10%. The accuracy grade of zero sequence voltage is 3p. Capacity requirements: capacity requirements: phase: ≥ 1va (600A / 1a), ≥ 2.5va (600A / 5A) zero sequence: ≥ 0.5va, meeting the matching requirements (considering the cable length of 12M, cooperating with FTU and line loss module, meeting the requirements of line loss measurement and fault judgment).
1.4 the configuration and interface adopt common box structure and spring mechanism. A set of current transformer is built in the circuit breaker to provide IA, IB, IC and I0 current signals; A set of zero sequence voltage sensor is built in the circuit breaker, the cable shall be fully sealed and waterproof structure, and the welding wire side shall be sealed with insulating material.
a. Ambient air temperature: - 40 ℃ ~ + 40 ℃;
b. Altitude: no more than 3000m;
c. The surrounding air can be polluted by dust, smoke, corrosive gas, steam or salt fog, and the pollution level is grade IV;
d. The wind speed does not exceed 34m / S (equivalent to 700pa on the cylinder surface);
e. The vibration or ground motion from the outside of switchgear and control equipment can be ignored;
f. The amplitude of electromagnetic interference induced in the secondary system shall not exceed 1.10kv.