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xkcd #2848: Breaker box
(imgs.xkcd.com)
Alt text:
Any electrician will warn you to first locate and flip the house's CAUSALITY circuit breaker before touching the CIRCUIT BREAKERS one.
Bold of them to assume there are that many circuits in any house built in my area. Most of the breakers will apparently control nothing, and then there's exactly one circuit that controls half the house, including the kitchen, so if you run the microwave and a blender at the same time, it'll trip.
I just got a giant, house-encompassing circuit like that broken up in my house. It ran the entire length of the front of the house, one wall each from two bedrooms, the entire living room, and one wall of the garage. Like who on earth ever thought someone would want all of these things controlled with the same circuit breaker? Getting it split up was the best money spent.
Someone from 1950 when there were only 3 items in existence that plugged into a wall outlet.