LW8-40.5 Outdoor High-Voltage SF6 Circuit Breaker

LW Series 40.5kV SF6 Circuit Breaker Product Introduction

1. Product Overview

The product features excellent breaking performance and adopts a pressure-type arc extinguishing chamber with a long service life. It can continuously break 40kA short-circuit current for 20 times without maintenance under rated voltage, without replacing sulfur hexafluoride gas. It has high mechanical reliability with a mechanical life of more than 6000 times and allows frequent operation; up to 12 current transformers can be installed per unit for users to choose from. The product adopts a new MKZMSF6 pointer density meter, and the pressure reading is not affected by temperature changes, making it easy to use.

The LW□-40.5 type horizontal SF6 circuit breaker can be numbered as LW8(A)-40.5, LW16-40.5, LW34-40.5 type; the middle-mounted type can be numbered as LW8(A)-40.5T, LW16-40.5T type. This type of circuit breaker is a three-phase AC 50Hz outdoor high-voltage electrical equipment, suitable for control and protection of 40.5kV/1600/2000 power distribution systems, and can also be used as a tie circuit breaker and a closing and opening capacitor bank combination. The circuit breaker is equipped with CT14 type spring operating mechanism. The product complies with the requirements of the national standard GB1984-1999 "High-Voltage AC Circuit Breakers" and the International Electrotechnical Commission standard IEC62271-100 "High-Voltage AC Circuit Breakers".

2. Normal Operating Environment

Altitude: not exceeding 2500m; high altitude type: 4000m;
Ambient temperature: -30℃~+40℃ (special requirements: -40℃~+40℃);
Relative humidity: daily average not more than 95%, monthly average not more than 90% (at 25℃);
Wind speed: not more than 35m/s;
Pollution grade: Grade III; creepage distance is 1050mm (1320mm) (the nominal creepage distance per kV is not less than 25mm/kV);
No occasions with flammable substances, explosion hazards, chemical corrosion and severe vibration.

3. Main Features of the Circuit Breaker

Excellent breaking performance, short breaking time, long service life, can continuously break 25kA for 20 times without maintenance under rated voltage, without replacing sulfur hexafluoride gas;
Reliable insulation, can withstand 40.5kV voltage for 10 minutes at zero gas pressure;
High mechanical reliability, strong closing and switching capacity, allows frequent operation;
No re-ignition for switching capacitor bank current for 400 times;
No re-ignition for switching long lines of 25 and 50 kilometers;
Simple structure, small volume, long maintenance-free period.

4. Main Technical Parameters

No.	Item	Unit	Parameters
01	Rated voltage	kV	24kV	36kV	40.5kV
02	Rated insulation level - Lightning impulse withstand voltage (full wave peak)	kV	150	170	200/215 (break)
02	Rated insulation level- Power frequency withstand voltage (1 minute)	kV	65	75	95
03	Rated current	A	1250/1600/2000/2500
04	Mechanical life	times	10000
05	SF6 gas rated pressure (at 20℃ gauge pressure)	MPa	0.20/0.45
06	Low pressure (at 20℃ gauge pressure)	Mpa	0.40
07	Minimum operating ambient temperature	℃	-30
08	Rated short-circuit breaking current	kA	20/25/31.5/40
09	Rated short-circuit making current (peak)	kA	50/63/80/100
10	Rated short-time withstand current (thermal stable current)	kA	20/25/31.5/40
11	Rated peak withstand current (dynamic stable current)	kA	50/63/80/100
12	Rated step-by-step breaking current	kA	50/63/80/100
13	Rated short-circuit duration	s	4
14	Closing time (under rated operating voltage)	ms	≤ 80	≤ 80	≤ 100
15	Opening time (under rated operating voltage)	ms	≤ 65	≤ 65	≤ 70
16	Rated operating sequence	-	O—0.3S—CO—180S—CO
17	Rated capacitor bank switching current	A	400
18	Annual air leakage rate	%/year	≤ 1
19	SF6 gas moisture content (at 20℃)	PPm(V/V)	≤ 150
20	Operating voltage of CT14 type spring operating mechanism	V	DC:110、220 AC：110、220、380
21	Closing coil rated voltage	V	DC:110、220 AC：110、220、380
22	Energy storage motor voltage	V	AC：220 DC：220
23	Closing speed	m/s	3.2±0.2	3.2±0.2	3.2±0.2
24	Opening speed	m/s	3.4±0.2	3.4±0.2	3.4±0.2
25	SF6 gas weight	kg	7-8
26	Circuit breaker (including operating mechanism) weight	kg	800/900/1400