There are three wires that connect an electrical socket to the main service panel in your house.
Black is hot, white is neutral, and copper or green is ground. The voltage between “hot” and neutral is 120V.
Theoretically, with this knowledge you can change electrical outlets all by yourself. But you shouldn’t, because it’s dangerous. You could get zapped pretty badly, and it’s painful, trust me.
There were signs lying around the Analog Electronics Lab that said “Danger: High Voltage”. I always thought they were kidding. I never touched anyone’s experiments anyway, out of respect.
One day I found out that the signs were real. Following that day, I was afraid to come near anyone’s high voltage experiment, because who knows when you could get electrocuted.
I was a lab assistant for a physics class at MIT in which the students did various experiments with electricity and magnetism.
In the class, the students had to build both a low-voltage power supply and a high-voltage power supply. Imagine a lab filled with 50 freshman students, most of whom have never soldered a circuit in their lives.
I was burned with soldering irons repeatedly, completely by accident. I also got shocked by many students’ experiments many times, also completely by accident. It was fun, though.
A couple of weeks ago, some folks from the power company came to my house to remove the old power lines and replace them with new ones.
I was told to move my car, because they would be cutting the power lines directly above it. I moved it to a place that I thought was out of the way, but then I was told that I had to move it to the other side of the street. Apparently, the power lines are longer than they seem, and if one falls on your car, it can deliver some shockingly high voltages to the poor little automobile.
So I moved it to the other side of the street. Then I went back inside to unplug my laptop, as I was told. I unplugged all the other appliances too, because it seemed like the right thing to do.
I watched out the window as a man dressed in protective gear carefully cut the old power lines and installed new ones. I was completely amazed. I cannot imagine working with high-voltage power lines all day. The stress of it would probably give me a heart attack. I would probably faint often, but the high-voltage shocks every now and then would probably resuscitate me anyhow.
High Voltage! is a place for me to store notes, thoughts, and random ideas about electronics. Sometimes there will be an emphasis on power electronics, but not always.
I am fascinated by high voltages, but I am also afraid of getting shocked accidentally. High voltages sure can be shocking, so be careful if you experiment with them!