| 摘要 |
<p>PURPOSE:To permit the application of the title line in an already installed trough and reduce the cost of installation by a method wherein an arc inducing metallic ring for shifting arc upon grounding a cable is attached to a water cooling tube provided in parallel to a power cable while the water cooling tube is ruptured by the heat of the arc shifted upon the grounding the cable to discharge water in the tube. CONSTITUTION:When grounding occurs in a power cable 2 in a trough 1, arc is generated in the metallic sheath of the power cable 2 and high-temperature arc heat is generated. This arc upon grounding is induced to the arc inducing acute end 9 of a metallic ring 8, attached to a position approximate to the grounding point of the cable sheath among a multitude of arc inducing metallic rings 8 attached to the water cooling tube 3 in lengthwise direction of the tube 3, whereby the arc is shifted. Accordingly, the water cooling tube 3 is ruptured by the heat of the arc whereby cooling water in the water cooling tube 3 is ejected. According to this method, the fire of the cable upon grounding the cable can be prevented easily with a low cost.</p> |
