Each 500 kV transmission line will be protected by two primary pilot relaying systems with a backup relaying to achieve primary and secondary protection.

由两个主控制继电保护系统对各条500千伏传输线进行保护，该控制继电保护系统上装有一只后备继电器，以实现初级保护与二次保护。

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American Electric Power plans to deploy Ti for the first time on a 765 kV transmission line in 2014.

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Meralco says it is not interested in the NPC's 230-kilovolt main transmission line, but just in the 115-kv subsidiary link to the southern Luzon provinces of Cavite and Laguna, where the country's major industries - Meralco's customers - are situated.

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