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[Jonathan Johnson]

...As this turns over - in the interim GU10/GU24 or the semi-proprietary orange connectors found in LED recessed lighting, the size of wire necessary for the much-reduced lighting load can get smaller and therefore cheaper.  5 amp breakers feeding LED lighting loads are more than sufficient, and this reduced wire gauge and reduced potential energy for fire or arc-flash are secondary safety benefits.  In the longer term, low voltage may replace line voltage, reducing shock potential as well.

Maybe this will provide economic incentive to separate fixed lighting circuits from convenience receptacle circuits. If electricians could install 5 amp circuits (and smaller, cheaper wires -- say 18 AWG instead of 14 AWG) for general fixed lighting, they would. They'd still have to install 15A or 20A circuits for general use convenience receptacles.

That would prevent the scenario like I have in my house, where the ceiling lights AND the outlets in a room are all on the same circuit, so there is no way (short of running a long extension cord from another part of the house) to change a light bulb without being in the dark.

[Speed Daemon]

I agree that economics plays a big role. I do think that there's a need for locking connectors in industrial environments, or else we wouldn't have Twist Lock, PowerCon or IEC 60309 "CEE connectors".

IMO, any "mission critical" industry that either can't tolerate the accidental disconnection during high current flow, or needs to prevent accidental power-off (think of every computer in a data center) should have locking connectors for both signal and power. Why can't pro audio gear have a standard "safe and secure" power connector that would be preferred for on-stage use? Something that would make it easy to declare the stage a no-NEMA zone.

[Lyle Williams]

A recessed receptical would probably prevent contact with the pins.

[Jonathan Johnson]

A recessed receptical would probably prevent contact with the pins.

Great idea! Now how do I plug this into your recessed receptacle?

[Jonathan Johnson]

Welcome to the United States, where every plug is designed to expose live conductors when only partially inserted.

Why can't some portion (5 mm maybe) of the prongs closest to the plug body be insulated, like they are in Europe? Maybe because the prongs are already as thin as they can be without overloading them or weakening them, so there's no way to effectively insulate them without seriously derating the plug. Nothing like living on the edge.

There is a potential solution that doesn't require redesign of the receptacles, and doesn't weaken the prongs. What it does do is increase the cost and potentially the bulk of the plug.

That is to design the plug with a retractable insulating sheath around the prongs. When you insert the plug into the receptacle, the sheath is pushed back into the body of the plug. This would shield the prongs when the plug is partially inserted.

The potential failure point of this has to do with the general weakness of the prongs. (UK plugs have much sturdier prongs.) If the prongs are bent, which is easy to do because they are so thin, the insulating sheath could break rendering the protection useless, or the sheath becomes jammed so it won't retract into the plug.

[Stephen Swaffer]

I agree that economics plays a big role. I do think that there's a need for locking connectors in industrial environments, or else we wouldn't have Twist Lock, PowerCon or IEC 60309 "CEE connectors".

IMO, any "mission critical" industry that either can't tolerate the accidental disconnection during high current flow, or needs to prevent accidental power-off (think of every computer in a data center) should have locking connectors for both signal and power. Why can't pro audio gear have a standard "safe and secure" power connector that would be preferred for on-stage use? Something that would make it easy to declare the stage a no-NEMA zone.

Who's going to volunteer to tell the guy with the vintage amp that he has to wack his NEMA plug off?

Seriously, some are already doing this with powercons.  I hear some don't like them-chances are you'll never get 100% agreement on anything-some will have to be forced to accept any new standard by way of being inconvenienced.

As for using lighter wire on lighting.  I am curious how things will play out.  In the typical home, outside of the kitchen and bath, how many appliances actually require a circuit capable of 1800 watts?  I don't know how long it will take-but I suspect that a low voltage supply complying with power limited rules installed in parallel with conventional 120 VAC-15/20 amp circuits would be the logical intermediate step-I would guess a different standard supply would be easier to sell than just a redesigned NEMA 5-15.  Perhaps a scenario where "wall warts" become optional-used in older homes, but able to be dispensed with in new homes?

[Speed Daemon]

Who's going to volunteer to tell the guy with the vintage amp that he has to wack his NEMA plug off?

A. If someone is touring with a real vintage amp for any amount of time, chances are good that whatever NEMA plug it has now isn't the one it came with. So if they have "wacked" it several times before, no big deal to do it yet again.

2. If someone wants to keep their vintage amp factory stock and take it touring, or if someone has removed the ground from their plug, I'd be the first to tell them that an isolation transformer will be their only power option. "Wanna use that NEMA 1-15P or 5-15P with the ground pole removed as-is? No problem, just say so on your rider, and hand over your prized bakelite plug to a qualified technician who will then make the unsafe connection, close and lock that side of the box for the duration of the gig, and then connect the safe side to the rest of the power distribution system."

When I made my suggestion, I was imagining having pagoda-style power boxes for the back line, with a top that opens up to expose the legacy sockets, and seals them in while in use. I've been dealing with professional electric guitarists / amateur electrocutioners for over 40 years now. I'm not the least bit shy about keeping them from electrocuting themselves and others onstage.

As for home lighting, I'm 100% LED in my house. I'm not in any hurry to tear out the conduit and 120V wires going to the overhead light fixtures in my old house, but sure can imagine new house developers loving the idea of using low voltage wiring for lighting. They save money, and get to promote it as energy-saving. And with structured wiring becoming more important, I can see flush-mounted AC wall outlets going away in favor of recessed connection points.

How about movable baseboards that slide or pivot to allow access to all electrical and optical cables? Instead of an electrician cutting holes for a new wall outlet, just flip up the baseboard and add a vampire tap outlet for low wattage appliances. With more and more things coming with USB power supplies, I could see having USB sockets everywhere, cleverly hidden in geometric designs.

[Lyle Williams]

Great idea! Now how do I plug this into your recessed receptacle?

That's the hard thing about safety improvements.  Getting 100% compatibility existing products is never easy (and often impossible.)

[Rob Spence]

Who's going to volunteer to tell the guy with the vintage amp that he has to wack his NEMA plug off?

Now that's funny.

NEMA and Vintage in the same sentence.

Ok, I am old... BN (before NEMA

Sent from my iPad using Tapatalk HD

[TJ (Tom) Cornish]

As for using lighter wire on lighting.  I am curious how things will play out.  In the typical home, outside of the kitchen and bath, how many appliances actually require a circuit capable of 1800 watts?  I don't know how long it will take-but I suspect that a low voltage supply complying with power limited rules installed in parallel with conventional 120 VAC-15/20 amp circuits would be the logical intermediate step-I would guess a different standard supply would be easier to sell than just a redesigned NEMA 5-15.  Perhaps a scenario where "wall warts" become optional-used in older homes, but able to be dispensed with in new homes?

Built-in things like lighting are easy as the application is known.  I think we'll get here sooner rather than later as the economic and installation time-saving benefits are already there.  On the receptacle side, at the moment every room is likely to have a high-drain device at least occasionally plugged in - a space heater or vacuum cleaner.  Vacuum cleaners could be battery powered; heaters not so much, but maybe multi-zone systems with a thermostat in every room replace that.

Low voltage is not a panacea either - USB is 5 volts, but 5 volts doesn't travel well.  Power over Ethernet is 48 volts which solves the distance problem for low to moderate loads, but still requires a voltage stepdown inside or outside the device for something like a cell phone.

In the future, maybe everything will be voice controlled and wirelessly powered so there will be nothing to plug in. 

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