What is an essential step before performing electrical measurements?

De-energizing the circuit being tested is an essential step before performing electrical measurements because it significantly reduces the risk of electrical shock and equipment damage. When a circuit is energized, there is a potential for electrical current to flow, which can pose hazards to the technician or engineer conducting the measurements, especially when making contact with the components or connections. By ensuring that the circuit is de-energized, you create a safer working environment, allowing for precise measurements without the danger of accidental electrocution.

In addition, working on de-energized circuits also allows for safer use of tools and equipment, which can lead to more accurate diagnostics and servicing of electrical systems. Depending on the situation, safety devices like lockout/tagout procedures may be utilized when de-energizing to ensure that no one inadvertently re-energizes the circuit while work is being performed.