Metal Oxide Surge Arrester
The metal oxide surge arrester is used to protect the 110kV gas
insulated switchgear from the damage resulting from atmosphere and
overvoltage. According to different installation methods, the
lightning arrester can be divided into the one with the line outlet
from the top and the one with the line outlet from the side.
Y10WF-100/260S, Y10WF-102/266S, Y10WF-108/281S
1. Installation place: indoor or outdoor;
2. Ambient temperature: -30℃～+40℃;
3. Solar radiation: the strongest radiation limit is 1.1 kW/m2;
4. AC frequency: 48Hz～62Hz;
5. The long-term voltage applied to the terminals in the metal
oxide surge arrester shouldn't exceed its continuous operating
6. Our surge protection device can work in areas where the seismic
intensity is no more than 7 degree.
7. Other conditions should be consistent with related requirements
of GB 7674.
Main Technical ParametersTable 1
The metal oxide surge arrester is supposed to completely meet the
requirements of GB11032-2010 and IEC 60099-4 (2006). The main
technical parameters are shown in table 1.
|Nominal voltage of the system kV (RMS)||Rated voltage kV (RMS)||Continuous-running voltage kV (RMS)||Nominal discharge current kA||Lightning impulse residual voltage ≤kV (peak)||Power frequency (resistive 1mA) reference voltage ≥kV(peak/√2)||1mA DC reference voltage ≥kV||Persistent current under Uc ≤A (peak)|
Structural Characteristics and Working Principle
1. The metal oxide surge arrester's core body adopts a circular
metal oxide varistor which has an excellent nonlinear
current-voltage characteristic. Through the single-column structure
fixed via an insulating support base and the external use of
explosion-proof tube protection, the components of the surge
arrester are fastened tightly together.
The core body is mounted with a shielding case for equalizing
internal potential distribution and electric field distribution,
and the entire assembly is encapsulated in a shell. After vacuumed,
the shell is filled with SF6 gas to ensure high insulation
strength. With protection from the metal shell, the performance of
the surge arrester is not influenced by the external environment
and thus ensures fine electrical properties.
Thanks to the reduced voltage peak between the arrester terminals
at steep impulse current conditions, the overvoltage protection
device offers larger range of protection for gas insulated
switchgears with flat volt-second characteristic curve.
2. With excellent nonlinear current-voltage characteristics, the
metal oxide varistor exhibits low resistance when over-voltage
arises in the power grid system, so as to reduce the system voltage
to the limited range to protect the power transmission and
transformation equipment. When the system operates under normal
conditions, the nonlinear metal oxide varistor will deliver high
resistance, and the current passing through the surge arrester is
just at a microampere level, thus the normal operation of the power
grid system is assured.
3. The external metallic shell delivers enough strength against the
internal pressure during an accident. The metal shell features high
yield strength and offers a fine sealing performance. We can also
install explosion-proof device according to the GIS or users'
requirements. When the internal pressure increases to a specified
value, the explosion-proof device is activated to release internal
pressure to avoid accident or corresponding impacts.
1. During transport, storage and installation, the metal oxide
surge arrester must be placed upright. Avoid external impacts or
collisions to protect inner components. If any similar phenomenon
is detected, carefully check the device to avoid any damage before
using it. When any damage happens, return the product to the
factory if necessary.
2. When delivering the lightning arrester in a vehicle, the vehicle
acceleration shouldn't be more than 3g. The speed shouldn't exceed
30km/h in case of poor road conditions.
3. In lifting the metal oxide surge arrester,