LW8A-40.5 Outdoor Porcelain Post HV SF6 Circuit Breaker
LW8A-40.5 outdoor porcelain HV SF6 circuit breaker
applies to the power system of AC 50Hz for the rated
voltage of 40.5kV to act as the control and protection
equipment as well as the interconnecting with circuit
breaker. The circuit breaker is fitted with CT for the aim
of measuring and protection. Adopting the structure of
single-pole single-column and single-break and the
principle of self-expansion arc-quenching, the circuit
breaker is fitted with CT14spring operating mechanism
and three-phase mechanical interlocking.
2. Model and meaning
2 Model and meaning
Design serial number
Outdoor SF6 circuit
3 Main technical parameter
No. Name Unit Data
1 Rated voltage kV 40.5
2 rated frequency Hz 50
3 rated current A 2000/1600/1250
4 rated short-circuit breaking current for lsc kA 31.5
5 rated short-time withstand current kA/s 31.5/4
6 rated peak withstand current kA 80
7 rated short-circuit making current kA 80
8 Near zone default breaking current kA lsc 90% lsc 75%
9 rated out-of-step breaking current kA 7.9
power frequency withstand Dry test 95
voltage for 1min Wet test 95
11 lightening impulse withstand voltage kV 185
12 rated operating sequence O-0.3s-CO-180s-CO
13 rated pressure of Sf6 20 MPa 0.50
breaking times of the rated
14 time 20
short-circuit breaking current
15 mechanical endurance time 3000
Medium voltage apparatus series
4 Service Environment Condition
3.1 Ambient temperature: 3.4 degree of pollution: not exceed degree ;
-3 0 ~+ 40 ; an d da il y temperature difference is 3.5 anti-seismic level: horizontal acceleration is 0.25 ;
not more than 25 . vertical acceleration is 0.125
3.2 Altitude: not exceed 2000m;
(for higher altitudes, please contact us)
3.3 wind velocity: not exceed 34m/s;
5 Main Characters
5.1 Self-expansion arc-quenching theory and excellent 5.4 Easy to mount and adjust, low noise.
breaking performance. 5.5 Reliable sealing.
5.2 Excellent electric performance and high insulation 5.6 Long mechanical life time and safe and reliable
5.3 High mechanical reliability, long period of mainten
-ance and little work for maintenance.
6.1 Arc-quenching Chamber fitted with the maximum of 12 current transformers for
The circuit breaker is outdoor porcelain post and each set for measuring and protection. Its winding is
every pole takes the shape of letter I. The current tran immersed in SF6 gas and the conductive pole is primary
-sformer (inside the porcelain sleeve of chamber) is circuit. The outgoing of secondary circuit passes through
fitted between the chamber and the post porcelain wiring board with good sealing performance to the out
sleeve and the three poles are mounted paralleled on -side and connects with secondary terminal board in
the base frame. Adopting vertical transmission method the mechanism tank by patch plug. There are two
and CT14 spring operating device, the mechanism tank types of transformers. They are LR-35 for measuring
is down the base frame. SF6 gas in the three poles is and LRD-35 with 10P for protection. LW8A-40.5 can be
interconnected through copper tube, which is in the equipped with 6 pieces of LR-35 and 6 pieces of LRD-35.
frame. Every type has four joints and three current ratios. Be
6.2 Current Transformer -sides these, we can satisfy the other special require
LW8A-40.5 porcelain post circuit breaker can be -ments of our customer after consultation.
7 Outline and Mounting Dimensions
8 Arc-quenching principle of CB
The arc-quenching chamber of circuit breaker is filled of the electric arc. To raise the mechanical efficiency
with 0.50MPa SF6, a kind of excellent arc-quenching and and decrease the operation power, the circuit breaker
insulation medium. The chamber adopts self-expansion is equipped with spring operating mechanism with
arc-quenching principle and makes fully use of the energy maintenance-free.
9 Operating Mechanism
The circuit breaker is fitted with CT14 spring operating 9.1 Breaking, making and re-closing operation can be
mechanism, which is mounted inside the tank and the made according to the requirement of the customer
mechanism tank is below the frame of circuit breaker. 9.2. Local and remote control
9.3. Manual breaking and making.
10 Order Notice
The following data should be specified when ordering: 10.5 Quantity, ratio, capacity and accuracy of current
10.1 models transformers
10.2 Rated electric parameters 10.6 The name and quantity of necessary spare parts,
10.3 Service environment conditions accessories, special tools and equipments.
10.4 Voltage of control supply 10.7 If you have special requirements, please contact us.