1.Brief Introduction

Type LW24- /T outdoor H.V. A.C. dead tank SF6 gas circuit breaker is a new kind of circuit breaker with self-blast interrupter and spring operating mechanismon the basis of technology of product imported from Mitsubishi, Japan.The latest achieve—arc extinguishing principle of gas-blast pressure adapting with breaking-current is employed,by which most of energy required for breaking rated short-circuit current are acquired from arc itself.Therefore, the demand for operating power is reduced significantly. The three pole interrupters are placed inside three metal enclosures respectively. The circuit breaker can be mechanically three-phase gang-operated. Both remote electrical control and local manual control can be realized. Type CT20-II spring operating mechanism, provided with the product, is a kind of mechanism with low operating power, minimum maintenance work needed and high reliability. The product reaches international advanced level in the respect of main technical performance.

LW24- 145/T passed the prototype appraisal by former Machinery Industry Department,Electricial Power Industry Department and National Science & Technology Committee in December 2008.
 

2.Normal Service Condition

2.1.Altitude:≤3000m

2.2.Humidity monthly:≤90%
2.3.Max .wind velocity:≤35m/s
2.4.Pollution class:IV class
2.5.Ambient air temperature:-35℃~40℃(It’s satisfied under condition of -40℃ in heavy cold area)
2.6.Max .temperature difference daily: 25K
2.7.Earthquake withstand density:9 degree
2.8.Ice coating: ≤10mm
2.9.Max. radiance from sun: 1000 W/m2
Note: When product is used under the condition out of above range, user and manufacturer shall consult to confirm.

3.Specification

4.Main Features and Advantages:

4.1.Thanks to excellent electrical field design and its perfect coordination with motion characteristics, breaking capacitive current may be without restrike. As for special breaker for switching capacitive load,back-to-back capacitor  bank breaking current may be up to 1500~2000A.

4.2.Gas-flowing characteristics is so appropriate that its breaking inductive current has no chopping overvoltage. As
for special breaker for switching inductive load, shunt reactor switching current may be up to 1500~2000A.

4.3. When breaking rated short-circuit current and any fault current,there are reliable breaking perfor mances and
abundant arcing time differential through application of arc-extinguishing principle of gas-blast pressure adapting
breaking current.

4.4.There are excellent insulation performances sand wide range of internal insulation margin.For 40.5kV product,the insulation level is corresponding to that of 72.5kV,which is used at decreased voltage.

4.5.Duration of rated short-time withstand current is as long as 4 seconds.

4.6.Due to high strength of outgoing porcelain and low gravity center of interrupter by horizontal configuration, the product has a high seismic-withstand performance with earthquake density of 9 degree.

4.7.The product is entirely provided with latest advanced type CT20 spring operating mechanism.So it has low
noise level,high mechanical reliability and mechanical three-phase gang-operation,and requires smaller space
occupied,compared to that of normal single-phase operated circuit breaker, specially suitable for urban power
networks and rural power networks retrofit projects.

4.8.After full routine test at factory,each circuit breaker is packed in a whole form with 0.05MPa SF6 gas filled in interrupter.Only some connection and re-fill of SF6 gas are needed on site,resulting conve nient commission. Maintenance work is minimized,which only needs to check SF6 gas gauge and apply lubricant.

4.9.The frame is such designed that the products are specially suitable for retrofit projects of replace ment of bulkoil
circuit breaker,such as type DW8-35,DW13-35 and DW2-35,etc,bulk oil circuit breakers, without foundation
reconstruction. Intermediate frame on support of type LW24-40.5 SF6 gas dead-tank circuit breaker is specially
designed so that the product can be installed directly on original foundation of former bulk-oil circuit breaker.Thus the
work for retrofit engineering is reduced greatly and project cycle becomes short.