Know your home's electric system

[unite for individuality]

How is it that this is not already part of the building/electric code?
This should have been made mandatory 100 years ago!
This should be required for all new construction,
and for all transfers of residency.
This should be required whenever a housing unit is
built, sold to a new owner, or rented to a new tenant.
It should apply to every single family home,
and to every apartment or condo.

You should do it yourself, every time you move into a new address.
What should you do?
Draw a diagram of the housing unit.
The diagram should include every outlet, light fixture, and installed appliance.
Then plug a lamp into each outlet, and turn on every light fixture.
Then, go to your power panel / breaker box / fuse box,
and turn off each circuit, one at a time.
Mark on your diagram which outlets, light fixtures, and installed appliances
turn off when you turn off which breaker, or pull which fuse.

You should also mark each circuit by whether it is fed by A or B power.
The power line to your home comes in three conductors -
hot A, neutral, and hot B.
The two hots are out of phase.
So, when you connect between either one of the hots, and neutral, you get 110 volts.
When you connect between the two hots, you get 220 volts.
Most stoves, electric dryers, and large air conditioners are connected to both A and B.
Everything else should be connected between either A or B, and neutral.

You can find out which circuits are fed by A or B power
by turning off the main breaker/fuse, one at a time,
and see which circuits go dark.
Most power panels / breaker boxes / fuse boxes,
have two columns of breakers/fuses.
Normally, all of the A powered circuits are in one column,
and all of the B powered circuits are in the other column.

You should map out your home's electric system
before you actually move in to a new address.
Do this before you pile a bunch of stuff in front of some of the outlets!
Make photocopies of the diagram.
Keep one at the power panel / breaker box / fuse box,
and keep other copies in convenient locations in your home.

[Elderberry]

You also may have  4 wire conductors feeding your house like mine. I discovered that Bastard Leg 3 Phase was powering my home. The only item running on 3 phase was my air conditioner.
Back when I bought my home in 1986 I looked up 3 phase for homes and found that Houston TX had more homes with 3 phase than any other city in the country. I now have a single phase air conditioner. I routed my 3 phase to my garage to run my equipment. One of the hurricanes that went through damaged the conductors feeding the house. When the conductors were spliced back together, they crossed 2 of the phases. It was lucky that the Bastard Leg was still on the same conductor, as the voltage of the Bastard Leg to ground is 212 volts, instead of 120, like the other 2 phases. That would have been very nasty feeding the house. The crossed phases powering my equipment in the garage would have caused them to rotate in the wrong direction. I told the tech hooking up the conductors to my house not to worry about the crossed phases, and I switched them myself at my breaker box in the garage.

Several times over the years, my 3 phase would go out, and it took a long time for an electrical repair man to come out. One told me that since I showed him that I actually utilized 3phase, I was grandfathered and they would have to continue to supply me with 3 phase.