
What is the most important rule of electrical safety?

The most important rule of electrical safety
Answer to Problem 1RQ
The power supply to an electrical circuit should always be disconnected before working on it.
Explanation of Solution
Description:
Power supply connection to an electrical circuit should always be disconnected before working on it. The following three steps can be followed to ensure the same.
To make sure that the meter is operating, test the meter on a known live circuit.
Turn off the power supply and test the circuit that is to be de-energized using a meter.
Repeat Step 1 to avoid any failure in operation of the meter.
To avoid accidental restoration of power by the people, install a warning tag at the point of disconnection. For added safety, use a lock to prevent anyone from turning the power back on.
Conclusion:
Thus, the most important rule of electrical safety is to de-energize the electrical circuit before working on it.
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Chapter S Solutions
Delmar's Standard Textbook Of Electricity
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