110kV-220kV系列額定電壓9-216KV金屬氧化物避雷器（以下簡稱MOA）是用于保護110KV電力系統的輸變電設備及變壓器中性點免受大氣過電壓和操作過電壓損壞的保護電器。
      該系列MOA由主體元件和絕緣底座等組成。主體元件內部采用非線性的金屬氧化物電阻片作為核心元件,它具有優異的伏安特性。當系統出現大氣過電壓或操作過電壓時，電阻片呈現低電阻，使MOA的殘壓被限制在允許值以下，同時吸收過電壓能量，從而對電力設備提供可靠的保護。在MOA的正常運行電壓下，電阻片呈高電阻，使流過MOA的電流很小，起到與系統絕緣隔離的作用。
      復合外套OA采用優質硅橡膠為原料，從而使產品體積小、重量輕、防爆性能大大提高，硅橡膠固有的憎水性使其具有良好的耐污性能。
      瓷外套MOA帶有壓力釋放裝置，MOA故障時內部壓力增大，防爆裝置動作，釋放內部壓力。電弧從內部轉移到外部，在瓷套外部形成短接，保證瓷套不炸裂。

      110kV-220kV series Rated voltage 9-216KV metal oxide surge arresters (hereinafter referred to as MOA) is used to protect the 110KV power transmission equipment and power system transformer neutral point from atmospheric over-voltage and over-voltage protection of electrical damage.
      MOA by the main elements of the series and insulated base and other components. Internal body components using nonlinear metal oxide varistor as a core component, it has excellent voltage characteristics. When the system when the atmosphere over-voltage or over-voltage operation, low resistance resistors showed that the residual pressure is limited MOA allowed value, while absorbing over-voltage energy to provide reliable protection for electrical equipment. MOA at normal operating voltage, the varistor resistance was high, the current flowing through the small MOA, the system plays the role of the insulating spacer.
      OA composite jacket made of high quality silicone rubber as a raw material, so that the products are small, light weight, explosion-proof performance greatly improved, the inherent hydrophobicity of silicone rubber it has a good stain resistance.
      Porcelain jacket MOA with a pressure relief device, the internal pressure increases when the MOA failure, explosion-proof device movement, release the internal pressure. Arc transferred from internal to external, external form in porcelain sets short, no guarantee porcelain burst.