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We need a lot more electricians

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Re: We need a lot more electricians

#421

Post by yamtaddle »

dionidium wrote: post #404
metadat wrote: post #388

Earlier quoted context omitted.

What are you talking about? GFCIs are integrated into the outlet. Did you mean something about chaining GFCI plug wiring? If it's even possible, such a wiring configuration seems like an obvious building code safety violation. For example: https://cdn.vox-cdn.com/thumbor/oGJ0LxRFZ9FNcRtpABAlXPnUApM=... Edit 1: If you're in Europe, my apologies - I have no experience with the wiring outside of the US. It sounds genuin…

Every GFCI outlet has a line side and a load side designed specifically for protecting additional downstream outlets. it's perfectly safe and legal (and a great way to protect multiple outlets, especially in older houses with ungrounded outlets). What OP is saying is that one of those downstream outlets can trip the GFCI and if you don't know which GFCI it tripped, then you have to go looking.

Right, that. And it's not like they're intolerable or anything, but they do represent a pretty high percentage of the time I spend messing with my house's electrical system. It's probably light bulbs (I swear, all but the crazy-expensive LED bulbs are blatantly lying about their lifespan, like by a literal order of magnitude) then GFCI stuff after that.

Re: We need a lot more electricians

#422

Post by Animats »

repiret wrote: post #344
Animats wrote: post #322

Earlier quoted context omitted.

> Even after the replacement was complete the electrician had to come back and redo the wiring connections because the inspector said the PVC joint at the top of the box had to be metal instead. Right. There must be a reliable metallic path to ground. This is a big problem with PVC pipe retrofits. In older houses, plumbing and conduit are metal and good grounds, and grounding to plumbing used to be permitted. Once PV…

> ... and grounding to plumbing used to be permitted Do you have a citation for this? I was under the impression that using plumbing as equipment ground was never allowed, but that conductive plumbing has required to be bonded to ground for some time. I was further under the impression that by code, plumbing repairs couldn't leave behind unbonded sections of conductive plumbing.

> ... and grounding to plumbing used to be permitted > > Do you have a citation for this?

You could look it up yourself. It's not hard.

Here's a guide to the 1981 National Electrical Code. See page 297. section 250-23, grounding for alternating current systems:

"grounding electrode conductor ... which runs to building steel and/or water pipe or driven ground rod".

Page 299, "water pipe and/or other suitable electrode" as grounding point for neutral.

Page 365, section 250-81 goes into water pipes as ground in more detail. It usually can't be the only ground. That's in 250-81(a). But back then, there was an assumption that water pipes were a path to ground.

By 2011, use of a water pipe as ground was more restricted. It's still allowed, but you have to attach directly to the metal pipe where it comes out of the ground. See[2], page 238, section 250-51, "Grounding electrodes". (You're allowed 5 feet of pipe from building entrance). Also see 250-53(D)(2), where the risk of future replacement of a metal water pipe with plastic is discussed. Water pipes are now valid grounds only if they meet the general ground rod criterion - six feet of conductor buried in earth. (3m for pipes.) You can see the general progression from "pipes are grounds" to "only grounding rods driven in the ground can be trusted." Which is reasonable enough, given that most new pipe is plastic. At this point, grounding pipes is more about preventing them from becoming energized if something shorts to a pipe. Just as all electrical boxes must be grounded.

[1] https://archive.org/details/mcgrawhillsnatio00mcpa/page/296/...

[2] https://archive.org/details/nationalelectric0000unse_d8w8/pa...

Re: We need a lot more electricians

#423

Post by nemo44x »

greedo wrote: post #381
nemo44x wrote: post #128

Earlier quoted context omitted.

Generally (in the USA) if you touch something in your home, you need to bring it up to code. You touch a wall, well now you need to make sure that wall has a socket in it, for example. Doing an addition? Well, now you need to ensure the entire house has fire/C02 detectors wired together with it.

This is not correct. I finished my entire basement, and nothing outside the basement needed to be updated to the current NEC.

I said addition, not finishing a basement. But if your basement had a wall that wasn't up to code and it was part of your finishing, you'd have to bring that wall up.

Re: We need a lot more electricians

#424

Post by bloomingeek »

My 2 cents: My home has a buried power cable from the late 60's. It's size can only handle up to 100 amps, my original main breaker was only 75 amp, we upgraded.(In my state all new houses have to have at least a 200 amp main.)

The electrical trade is very rewarding, but very dangerous. You typically have to rely on co-workers to be responsible and safe, if they are distracted, life changing and/or ending results can occur.

Before considering an electrical career, attend an arc-flash class to get an idea about what your are signing up for.

If you are a detail person, it's a great trade. If you like working in all sorts of environments both in and outdoors, it's a great trade. It will take a long term toll on your body because of the mechanics of the jobs.

Re: We need a lot more electricians

#425

Post by toss1 »

Johnny555 wrote: post #410
londons_explore wrote: post #75

Earlier quoted context omitted.

> likely have some non-compliance with the current electrical code. It frustrates me that every year quite a lot of people are killed due to old houses not having whole-building GFCI's. A GFCI costs only $20 and can be installed inside 10 minutes. So it seems crazy to be letting people die... Yet typically electrical regs require that if an electrician installs a GFCI, they bring the whole house up to modern standard…

It frustrates me that every year quite a lot of people are killed due to old houses not having whole-building GFCI's A whole building GFCI sounds like a bad idea, throwing the entire house into darkness as well as cutting off the refrigerator and HVAC because a contractor plugged in a damp power tool in an outside outlet sounds like a bad idea. Worse if you were out of town when it happened.

THIS!

Whole building GFCI - that is just nuts!

There are many ordinary motors that will leak just a bit to ground, enough to trip the GFCI, but no hazard exists — this would mean disabling the whole building, computers, refrigeration, water pumping, etc. just turning on that device. I've actually got one in a treadmill, and also a wood router tool - they trip the garage GFCI every time. At first I was concerned and "what's wrong with these things?". but as far as I could read, there is no issue, just an issue with certain types of motors that is no hazard, but a basic incompatibility.

And yes, being able to kill the entire power to the house merely by plugging a device into one of the outside outlets would be an insane vulnerability, not just by the contractor's accident you mentioned, but also by deliberate action - great way to start a burglary or home invasion, don't even need to find a wire to cut.

Yikes!

Re: We need a lot more electricians

#426

Post by simeonf »

idiotsecant wrote: post #196
jxramos wrote: post #159

Earlier quoted context omitted.

why's that, is there some guarantee they fail to live up to? Is there something probabilistic to them or something?

GFCIs have a simple and well defined function. What is the current through one lead? What is the current through the other lead? Do they differ by more than x amount? If so, trip. AFCIs are a whole different thing - the plug is trying to predict when arcing is happening somewhere downstream of it and it has very little in the way of 'processing' power to do it, so generally there is a classical filter that is designe…

Agreed on AFCI circuit breakers! They are now mandatory for all 15-20 amp light and plug circuits on new construction where I live - although breakers for large appliances do not require them. But I have several portable tools (eg a carpet cleaner) which will make an AFCI breaker trip every time. AFCI circuit breakers seem to be more fragile (read the box: much smaller range of acceptable heat and limited number of duty cycles) - I apparently killed one just by tripping it repeatedly. And while a regular 15 amp breaker is a few bucks, the CAFCI breaker I'm supposed to use is $45...

Re: We need a lot more electricians

#427

Post by api »

ilyt wrote: post #158
api wrote: post #41

Maybe we can retrain the vast number of auto mechanics and gas station people we will no longer need?

EVs still need service, just different kind. Sure, some will be fired but in most cases it will be just getting new skillset required for EVs

They overall need a lot less service than gas cars. No oil changes, far fewer moving parts, simple or no transmission, etc.

Re: We need a lot more electricians

#428

Post by squokko »

ilyt wrote: post #101
londons_explore wrote: post #75

Earlier quoted context omitted.

> likely have some non-compliance with the current electrical code. It frustrates me that every year quite a lot of people are killed due to old houses not having whole-building GFCI's. A GFCI costs only $20 and can be installed inside 10 minutes. So it seems crazy to be letting people die... Yet typically electrical regs require that if an electrician installs a GFCI, they bring the whole house up to modern standard…

There is a good chance that if you installed GFCI in some old house it would just... trip due to shitty wiring. But yeah, the law should probably have exception for installing safety devices, it's better to have some than zero because someone can't afford it.

If it would just trip, then the house wiring is a hazard! I suppose you can choose to live in it but if at all possible you should not.

Re: We need a lot more electricians

#429

Post by nemo44x »

greedo wrote: post #414
nemo44x wrote: post #183

Earlier quoted context omitted.

> It's just the cheap teflon stuff that's out of luck. And copper and aluminium. Some stoneware too as well as glass when needed.

Copper and aluminum can be used as a cladding around the ferrous metal core just fine. I guess you could do the same with some of the ceramics/stoneware as well.

It really isn't just fine. You lose the entire purpose of the pans and might as well be cooking on an electric stove at that point.

Re: We need a lot more electricians

#430

Post by russdill »

rootusrootus wrote: post #367
russdill wrote: post #238

Earlier quoted context omitted.

Even with the same size breakers you have to be careful. Many circuits in the US are wired using a shared neutral. These circuits must not share the same phase and when rewiring an entire panel this seems like it'd be an easy mistake to make.

Multiwire branch circuits must be wired with tied breakers. If the person rewiring doesn't understand that this must be duplicated in the new panel, they definitely has no business upgrading their own panel.

This doesn't appear to have been the case until 2008, at least with multiwire branch circuits that supply separate outlets. Many if not most 100A panels with multiwire branch circuits will have been wired with breakers without ties.
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