I need to replace a faulty breaker. Here's a picture of my main breaker box. There's no master switch that I can see that shuts off power to all of the breakers.
Following the line up and out of the box, it runs along the basement ceiling and out through a hole in the foundation.
Let me know if you need to see something else.
Edit. Resolved! I found a master switch on the outside of the house in a panel adjacent to the meter. Weird that anyone can just walk up to my house and turn all of the power off.
The other poster is correct in that the master breaker may be elsewhere. It will be on the path of the two big wires coming put of the top there, wherever it is they go in your house. Probably right on the other side of where the incoming line goes through the wall.
But I actually came here to say I have never once in my life shut off the master to replace a breaker. Remove the hot wire from the dud breaker first and then that circuit is dead. Just don't touch the bus bar in the back of the box and you'll be fine.
If you suspect shenenegans re: things being hot that shouldn't be, you can verify with your multimeter or voltage probe before touching anything.
Osha always talks about how its not the first mistake that kills you, and I think in the case of home electrical, leaving a panel energized while your hands are in it, would count as number 1.
Hands is the mistaje there. Always use one hand only when working on live wires. The hand that you are not loojing at gets into trouple. plus your shoes probably are insulated enough to make shocks annoying but not harmful.
I knew two electricians who used to say this kind of stuff.
"knew"
Hopefully they could say other stuff after the day they stopped saying that.
Your getting downvoted, but you have to be trying pretty hard to electrocute yourself by swapping a breaker.
To wit, I haven't managed it yet.
The rub is, it's inevitable you have to mess with the damn thing when the rest of the household is thoroughly active. Interrupting power to every other circuit and appliance in the place is often simply not an option. Especially once the obligatory hardware store trip to get the new breaker -- bringing the old one with you to match it up -- enters the equation.
When you remove the hot wire from the breaker the wiring is by definition dead unless you have transient voltages from elsewhere that should not be there. If you do, you have deeper problems. Plus, you should do so with the breaker in question off anyway (and if you have a dud one, the only reason you knew about it was because it failed open circuit in the first place, so it's already off). The breaker's casing is extremely well insulated, and no part of the operation requires touching anything except insulated wire or the plasic breaker casing itself.
People also thoroughly overestimate the danger as if there are magically somehow different volts inside the panel than out of it. Yes, you can theoretically touch 240v if you manage to grab both bus bars at the same time. Otherwise, the shock you may deliver yourself is literally no different from mis-grabbing a normal plug via touching its prongs while it is partially inserted in an outlet, which is I'm sure something everyone has done at least once in their lives.
You should still know where your home's master breaker is located anyway, of course, in case there is some other catastropic emergency.