What does 'de-energized' mean in the context of signal maintenance?

What does 'de-energized' mean in the context of signal maintenance?

• A. No voltage is present on the equipment; energy sources are isolated.
• B. The equipment is energized but under no load.
• C. The equipment is in standby mode.
• D. The equipment has residual charge.

Answer: (A)

De-energized means you have removed all power from the equipment and isolated every energy source so nothing can re-energize while you work. In practice, you verify this by checking that there is zero voltage on the equipment and by ensuring all power paths, control circuits, and energy sources are locked out or tagged out. This creates a safe baseline for maintenance. This state is the best choice because it explicitly covers both the absence of electrical energy and the deliberate isolation of sources that could re-energize the device. Other situations don’t describe a true zero-energy condition: being energized but without load means voltage is still present; standby implies the system could be powered back up; and residual charge refers to stored energy that may still exist even after isolation, which requires additional procedures to discharge.

De-energized means you have removed all power from the equipment and isolated every energy source so nothing can re-energize while you work. In practice, you verify this by checking that there is zero voltage on the equipment and by ensuring all power paths, control circuits, and energy sources are locked out or tagged out. This creates a safe baseline for maintenance.

This state is the best choice because it explicitly covers both the absence of electrical energy and the deliberate isolation of sources that could re-energize the device. Other situations don’t describe a true zero-energy condition: being energized but without load means voltage is still present; standby implies the system could be powered back up; and residual charge refers to stored energy that may still exist even after isolation, which requires additional procedures to discharge.