保定市伊诺尔电气设备有限公司

电缆接地箱作用及特点

Function and Characteristics of Cable Grounding Box

       电缆接地箱，用于电缆护层的保护接地，是保护电缆护层的专用装置，避免雷击及感应过电压对电缆护层的危害。电缆接地箱里面包含连接铜排、铜端子以及电缆护层保护器等。

Cable grounding box, used for protection grounding of cable sheath, is a special device for protection of cable sheath, avoiding the harm of lightning strike and induced overvoltage to cable sheath. The cable grounding box contains copper bars, copper terminals and cable sheath protectors.

       单芯电缆：35KV大截面电力电缆、66KV、110KV及以上的电压等级的电力电缆都是单芯电缆。单芯电缆一般是一端三相并联接地，而另一端不接地，所以当雷电流过电缆内部时，电缆没有接地的一端会出现很大的冲击过电压及工频感应过电压，过大的冲击过电压和工频感应过电压会给单芯电缆带来严重危害，大大缩短电缆的使用寿命。

Single-core cable: 35KV large cross-section power cable, 66KV, 110KV and above voltage level power cables are single-core cables. Single-core cable is usually grounded in three-phase parallel connection at one end, while the other end is not grounded, so when lightning current passes through the cable, a large impulse overvoltage and power-frequency induction overvoltage will appear at the ungrounded end of the cable. Excessive impulse overvoltage and power-frequency induction overvoltage will bring serious harm to the single-core cable and greatly shorten the service life of the cable.

       保护措施：为限制电力电缆金属护层上的感应电压和故障过电压，并避免在护层中形成环流，电缆护层一端直接接地，另一端则须通过保护器接地。如果线路较长，可以将电缆护层分三段（或三的倍数段）相互绝缘，分段处的护层交叉互联后通过保护器接地。

Protective measures: In order to limit the induced voltage and fault Overvoltage on the metal shield of power cable and avoid circulating current in the shield, one end of the shield is directly grounded and the other end isposuiji.89ix.com xiangbao.37ix.com.cn kongtiao.71ix.comqingwuji.89ix.com paimen.89ix.com kongtiao.37ix.com.cn grounded through the protector. If the line is long, the cable sheath can be divided into three sections (or multiple sections) to insulate each other, and the sheath at the sections can be interconnected and grounded through the protector.

        电缆护层保护器：保护器采用ZnO压敏电阻作为保护元件，无串联间隙，保护特性好，具有优良的非线性伏安特性曲线。既具有瓷套式金属氧化物避雷器的优点，还具有电气绝缘性能好、介电强度高、抗漏痕、抗电蚀、耐热、耐寒、耐老化、防爆等优点及良好的化学稳定性、憎水性、密封性。

Cable sheath protector: The protector uses ZnO varistor as protective element, without series gap, has good protective characteristics and excellent non-linear volt-ampere characteristic curve. It not only has the advantages of ceramic sleeve MOA, but also has the advantages of good electrical insulation, high dielectric strength, leak resistance, corrosion resistance, heat resistance, cold resistance, aging resistance, explosion resistance and good chemical stability, hydrophobicity, sealing.

电缆接地箱的特点：

Characteristics of cable grounding box:

1. 电缆接地箱的材料采用不锈钢板和特种绝缘材料。机械强度高，绝缘性能好，有较好的密封防水性能。

1. The material of cable grounding box is stainless steel plate and special insulation material. It has high mechanical strength, good insulation performance and good sealing and waterproofing performance.

2. 电缆接地箱内部导电部分采用的是铜板连接，所以电阻小，导电性能好。

2. The conductive part of the cable grounding box is connected by copper plate, so the resistance is small and the conductive performance is good.

3. 电缆接地箱内部的电缆护层保护器。能有效防止电缆护层过电压。

3. Protector of cable sheath inside cable grounding box. It can effectively prevent overvoltage of cable sheath.