New Video! The GFCI/RCD

If you might find interesting this anecdote: in Italy these devices are called, in colloquial/slang, "salvavita" - lifesaver. The install has been made compulsory in 1990

My house's hot tub (located the US) has a 240V double breaker with an integrated GFI. Oddly, it only has a test button, and no reset button. Presumably it trips the whole breaker and you reset it by just turning the breaker back on. There is no "test monthly" wording anywhere on it, which I find a little disturbing.

nobody

obvious protection isn't always the case. I've seen upstairs bathrooms with regular outlet protected by a GFCI in the downstairs bathroom. My house has an addition that had a hot tub in it, so everything needed to be GFCI. All the GFCIs are in the basement. There's even one for the lights and the fan, which are 10ft up.

adcurtin

Here in Australia every circuit in the house has a "safety switch" installed as part of the main circuit board feeding power throughout the house. Every circuit is "safe" no matter where it's placed with the dwelling.

I loved the main content, but also the little jokes here and there. [Will I ask a fourth question?" "In the shape of an L of her forehead."] Not only do we get a good technical overview, but it's extremely fun to watch!

Kevin Kostka

As I replied to Andy, I think some of the reason we don't think to put it in the breaker panel is that 120V electricity tends to be safer. With dry hands, getting a zap from 120 is rarely serious. So rather than protect every circuit, we just protect where the advent of wet skin increases the chances of a lethal shock. Not saying that's good, but it's probably the reason.

Technology Connections

My gut feeling is that because we use 120V on general circuits, there a higher default safety level. And yes, I know that it's current that kills, not voltage, but a higher voltage penetrates farther into the body so in general lower voltage is safer. When around water, though, the insulating effects of your skin are greatly negated, hence the requirement of GFCI's. I have on a few occasions touched a live 120V wire with no ill effects--and I witnessed the same thing happen to my dad. With dry hands, it's dangerous alright, but usually not lethal. Just mildly painful and surprising.

Technology Connections

Prepare yourself for a YouTube comments section full of hate for US electrical codes. Has anybody actually studied this? I wonder how the US actually ranks in terms of electrical accidents worldwide.

Andy Aspaas

Interesting video, as always. So apparently the standard in Germany is a RCCB (Residual Current operated Circuit-Breaker, commonly referred to as a "FI-Switch") and they are located in the fuse box so every socket is protected by it. It's pretty surprising to me that not every socket in an US household is protected by this or something similar. Yes, if you have a faulty device you have to search for it but it isn't that hard because you still have the normal circuit breakers. Switch them all off and then on again one by one and when you get to the circuit with the faulty device the RCCB switches off again. So you can delimit the problem to a single room or area pretty fast. And I prefer to search for a faulty device for a few minutes to getting an electric shock because the socket wasn't protected.

Robert

"Will I ask a fourth question?" LOL, Alec. :-) We also call them ELCBs in the UK. Earth Leakage Circuit Breaker.

Stephen Bell

Thanks for reminding me. Let's see if this wo

K.o.R

Thanks ! You certainly are an excellent taecher

Staffan Ahlstrom

As an electrical engineer, I love your demo!

Michael Steeves

Well I just tested the GFCI in my bathroom. Thanks for the reminder.

I had to look this up! Apparently they can detect when electrical arcing is occurring within a circuit, which is a leading cause of electrical fire. Actually pretty neat, since this is exactly the sort of fault a circuit breaker won't detect, yet sparks inside a wall or next to a stud could surely cause a fire.

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I heard a contractor talking about having to install GFCI and Arc Fault. What is the difference?

Rich Jeanes