How to make sure the electrical power is off? Even before you touch a wire?
The answer is a Non-Contact Voltage Tester.
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Usually when you need to replace a light bulb or a light switch, the most important two steps are
1.Turn off the power of the light at the main panel.
2. Always remember to double check. Use a voltage tester to test and make sure you do turn off the right one. Otherwise…… Ouch
A Non-Contact Voltage Tester is cheap and easy to use. The cost around 10 bucks may save your life. In the past, there are CONTACT voltage testers. But nowadays, you should have a non-contact version to secure your safety.
Usually the tester is powered by batteries. Using a normal receptacle to see if the battery is still alive is necessary. The tester will flash, usually red, whenever it comes close to a hot wire. Here’s how to use it.
Situation 1: Test a receptacle. A receptacle has three holes, one of the hole is HOT. Your voltage tester will flash and tell you if the electricity is on.
Situation 2: Test Extension Cords
Situation 3: Test Cable