What must be ensured before phasing and tying two electrical lines together?

Phasing and tying two electrical lines together is a critical task that must be approached with caution to ensure safety and reliability in the electrical system. The correct choice emphasizes the importance of having both lines energized before they can be properly phased and tied.

Energizing both lines allows for the determination of phase alignment. This process involves verifying that the electrical phases of each line are compatible. If both lines are energized, it can be confirmed that both are operating at compatible voltages and frequencies, which is essential for preventing electrical faults or outages when connecting them.

Ensuring that both lines are energized not only aids in confirming phase alignment but also facilitates real-time monitoring of electrical parameters that can impact the safety and functionality of the connection. This is particularly important in high-voltage systems where misunderstandings about line voltages can lead to severe consequences.

In comparison, grounding or disconnecting the lines would prevent them from being energized and make it impossible to properly phase and tie them. Inspecting for corrosion, while important for overall maintenance, does not address the immediate requirement of ensuring phase compatibility between live lines. The primary focus in this scenario is confirming energy status to effectively align the phases of the two lines.