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by rootusrootus 1497 days ago
> lightswitches can be just as dangerous as breaker panels

That's very much not the case. A light switch, at least in the US, is just 120V. Sure, it could kill you, but 99.999% of the time it'll just annoy you if you touch the hot wire inadvertently. You can easily get 240V inside the panel, however, and on top of that you can easily get it at 200A. I'm a lot more careful when I've got the panel cover off for any reason.
2 comments
tlb 1497 days ago
There isn't 240V to ground, which is the usual path for shocks. To get 240V through your body, you'd need to touch two hot wires at the same time. And you feel it when you touch the first one, so I think this is rare. You should be working with one hand most of the time.

The 200A is a danger. A direct short from a bus bar to ground can peak at 1000s of amps before the main breaker blows.

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quesera 1497 days ago
True, and of course it only takes a small fraction of one amp to cause harm to a human, if the path of the current crosses your heart or lungs.

240V at 200A would burn you crispy, but it's a bit challenging to get to.

120V at a fraction of 1A can disrupt/stop your heart, and it's easy to get inside a service panel.

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quesera 1497 days ago
OK, but no one is talking about working on the inside of panels.

It's been clear throughout the thread, but yes -- don't open breaker panels and work on them casually.

Flipping a breaker in a closed, code-compliant panel is exactly as safe as flipping a lightswitch in a closed, code-compliant wall box.

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rootusrootus 1497 days ago
> OK, but no one is talking about working on the inside of panels.

I must have misunderstood, then -- you said light switch wiring is as dangerous as breakers, and breaker wiring can only be found inside the panel.

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quesera 1497 days ago
It won't be particularly rewarding, but if you go back through the history you will see the full context.

It involves the safety of requesting an inexperienced person to flip breakers.

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rootusrootus 1497 days ago
Sure, I get that. But the wiring in a panel is just as hidden as the wiring of a light switch.
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quesera 1496 days ago
This was exactly my point. :)
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