Ideal Household Electrical Standards?

Username1

100 W
Joined
Nov 26, 2013
Messages
168
Disclaimer: This thread is purely for fun and autistic contemplating!
I was thinking about home electrical, and what's best standard in theory if a country was starting from scratch, with similar power levels as today. Here's my idea (remember I'm no expert). What do you think, and let's hear your own ideas!

-------------------------------------

Voltage and Type
I propose a single voltage of 100 VDC for a balance of safety and practicality. There should be very little chance of dying from 100 VDC, even with unfavorable factors like sweaty hands. Unlike AC, it requires you to touch both ends at once to get shocked, and it doesn't pulse meaning it's much less likely to stop your heart. 100 VDC is also high enough to feel but without significant pain, which is kind of a safety feature (you could touch >50 VDC and be unaware it's live).

Although this would require thicker wires, you'd only need 2 instead of 4 (no neutral or ground). So even though the wires need to be 2.4 times bigger (compared to 240v), you only need half as many, making it similar overall. I don't believe DC requires a ground wire, correct me if I'm wrong.

-------------------------------------

Receptacles
Receptacles (and breakers) would be labeled by their continuous power rating, instead of the non-continuous amp rating used now. Currently all receptacles use dedicated circuits and single outlets with the exception of 120v (usually). I propose expanding this to all receptacles. This means you'd always know how full the circuit is without checking the household wiring and other receptacles. These features (combined with being DC power) would make home electrical extremely easy to understand (and even work on) for regular people.

1 kW and 2 kW together would replace the 120v receptacle, with the former being placed throughout the house, and the latter being placed in certain spots for low power appliances (bathrooms, kitchens, etc.). 4 kW and 8 kW would replace 30a/50a 240v receptacles for regular appliances. 16 kW would replace the (rarely used) 60a 240v receptacle, used for fast charging EVs. Devices over 1 kW would plug directly into their receptacles, while devices under 1 kW would usually use power bars to create enough outlets for all your various devices.


1 kW - The primary receptacle used throughout the house for most things.
- electronics, fans, lamps, fridges/freezers, small washing machines

2 kW - A common secondary receptacle for low power appliances.
- large washing machines, dishwashers, window ACs, space heaters, countertop appliances, hair dryers, power tools

4 kW - A receptacle for medium power appliances.
- dryers, small ovens

8 kW - A receptacle for high power appliances.
- large ovens, EV charging

16 kW - A receptacle for EV charging.
- EV charging
 
Household switches would be large, heavy, expensive, and short-lived. There would be substantial transmission losses if distribution were DC, and substantial local rectification costs if distribution were AC and residential service were DC.
 
Chalo said:
There would be substantial transmission losses if distribution were DC, and substantial local rectification costs if distribution were AC and residential service were DC.

Yeah this topic is just about inside the house, not distribution. What kind of losses would you get from converting powerline AC to household DC?

Chalo said:
Household switches would be large, heavy, expensive, and short-lived.

By switches I assume you mean light switches? How expensive would a durable DC switch be, compared to an AC switch?
 
Larger wires needed for dc then ac
Shorter conductor distances for dc then ac

Remember that ac hits zero 60 times a second, dc never hits zero, so its quite easy to unlatch a switch when its on ac.
With dc, every single time there would be a spark, damaging the switch every time its used.
 
calab said:
Larger wires needed for dc then ac
Shorter conductor distances for dc then ac

I didn't know that DC of the same voltage requires bigger wires. Why is that? Surely it can't be much of a difference.
 
Regarding switches:

DC never shuts off current; the switch has to do all the work, must move contacts farther apart to break arc, must survive arc the entire time, heats up more as arc lasts longer, wears out faster as arc eats contacts.

AC shuts off current at the frequency it's cycling at, so the switch disconnects at that point and it happens so many times a second it only has to pull contacts apart a tiny amount to break arc. Much smaller, much less wear.

Same for circuit breakers and fuses and connectors.

(arcs are hot; we use them for welding)

There are significant differences between AC and DC operation of devices; some, like the above, give good reason for not using DC this way.
 
In my opinion home electrical should be based primarily around human safety and simplicity of installation. There's a very narrow sweet spot where this is possible, somewhere around 100v DC. Going much higher in voltage you lose the safety, while going much lower you lose sufficient power (with reasonably sized wires).

If it costs a little more in copper, switches and breakers so be it. I doubt the costs would be untenable. Due to being much safer, electrical work could probably be done without a licensed electrician. The panel would be hooked up by an electrician, then general contractors or even home owners could do the rest (still subject to inspection). Or maybe have a short course for home electrical that's much easier to obtain. Either way, this would save a lot of money and maybe offset the extra material costs.
 
Convince people to reproduce at less than replacement levels, and then we can discuss soaking extra per capita infrastructure costs.
 
Chalo said:
Convince people to reproduce at less than replacement levels, and then we can discuss soaking extra per capita infrastructure costs.

Supposedly this is already the case everywhere but the 3rd world, with immigration currently offsetting that in 1st world countries.
 
Not safer, for the same reason as the switches work the way they do.

DC won't let go if you touch it; AC can, as outlined for the switches.

(meaning, with AC if your muscles spasm, you have a chance to let go everytime the current stops. WIth DC the current never stops, so a spasm won't either, until the tissue cooks enough to stop operating...or you're dead.)

Go down to the "12v" RV type systems and such, and then you might have a point. ;) But the the current would be a decimal place higher, and wires, switches, connectors, etc., would all be that much bigger, too.

Username1 said:
In my opinion home electrical should be based primarily around human safety and simplicity of installation. There's a very narrow sweet spot where this is possible, somewhere around 100v DC. Going much higher in voltage you lose the safety, while going much lower you lose sufficient power (with reasonably sized wires).

If it costs a little more in copper, switches and breakers so be it. I doubt the costs would be untenable. Due to being much safer, electrical work could probably be done without a licensed electrician. The panel would be hooked up by an electrician, then general contractors or even home owners could do the rest (still subject to inspection). Or maybe have a short course for home electrical that's easier to obtain. Either way, this would save a lot of money and maybe offset the extra material costs.
 
I think that's the conventional take everyone's heard, that DC clamps you while AC gives you time to release. I'm not so sure though, as I've also read it can be untrue or even the opposite. AC pulses at 60hz, which continually contracts and loosens you muscles with very little time in between. If you grab on with enough voltage and current, I don't see how you let go. I've also heard that DC can cause you to dramatically tense up once then let go. I'm not entirely sure.

Either way 100v DC (or similar) seems very unlikely to cause that kind of contracting. DC is safer than AC of the same voltage because AC's peak voltage is significantly higher. From what I've seen AC also penetrates your body more easily because of your body's capacitance, whereas this doesn't happen in DC. I've also read that AC can disrupt your heart much more easily due to it trying to make your heart beat at 60hz, causing it to be deadlier than an equal amount of DC current across the heart. Isn't cardiac arrest the main danger and cause of death from residential power?
 
Username1 said:
Isn't cardiac arrest the main danger and cause of death from residential power?
I would have thought residential power-caused fire as the main danger and cause of death from residential power. No?
 
Its my understanding that 60V is an approximate limit to where electricity will penetrate dry human skin.

Many variables, for instance if you are sweating, the salty water is highly conductive. Of course, skin thickness varies from person to person.

The old adage that I have been taught is that if you touch a light bulb socket with your finger, and you short the positive nipple to the threaded shell...120V AC will not damage your finger (don't try this). My brother tried this as a kid, and he said it hurt, but his finger still works.

Ive heard old electricians say they have done this on purpose to see if a wire was 110 or 220, since 220 hurts more (again, fo NOT do this). However they were shorting across only one finger.

If you short current from one hand over to the other hand, the current passes across your heart, and your heart will stop beating due to its electrical signal getting scrambled.

Builders have posted here that 72V DC batteries have been shorted by accident, and they didn't feel it through their skin, which gives me confidence in the 60V standard. I suppose there are many different modifiers to that danger.

Many people have died from a 120V AC electrocution, so that is a DEFINITE hard danger zone.

Also, you can get a burn from "safe" voltage if the amps are high. There are youtubes if 12V DC car batteries rated for 800A to start a car, and when shorted with a steel clothes hanger, the steel glowed and melted.

Since step-down converters are fairly efficient, and many models of electric car use a voltage around 380V, then I would suggest a garage main voltage of 440V AC.

Zero motorcycles use 28S / 102V DC, partially for the simpler BMS, and I believe partially for the common 120V AC in garages.

120V and 240V can both kill you, so...I dont have a preference, but I think 240 would be nice because more volts in a device can sometimes mean fewer amps...
 
spinningmagnets said:
Builders have posted here that 72V DC batteries have been shorted by accident, and they didn't feel it through their skin, which gives me confidence in the 60V standard. I suppose there are many different modifiers to that danger.

I can feel painful sensation (that is difficult to describe) from just some of the cells in my EIG NMC pack, when I have accidentally put my dry palm across the busbars from cell to cell on the top of the pack (given the size of my palm and the setup of the busbars, it couldn't be more than 7 or 8 cells in series, if that).

On the occasion I was stupid enough to pick up my spare pack (EIG NMC 14s 2p, ~35-40lbs) by the main +/- busbar ends (if they weren't electrified, they'd make great handles, nice and stiff :lol: ) with my bare but dry hands, I got quite a shock from it, and I had a hard time letting go of it; my hands wouldn't obey me correctly. I was able to pull my hands away from it but not to set it down, so it dropped the short distance back to the ground. It was not like the tingle or kazowie you get from an AC-wall-voltage shock; it was a sensation as if something else was controlling my muscles and disabling my access to them, while still letting me tell what was going on. And it hurt, quite a bit, mostly during the event, but for a while afterward. I don't know if I could've let go of the pack at all if it were a hundred volts or more. Not going to test the theory.


I've been shocked by wall AC voltage more than once in my life, both single and dual phase, and that was no fun either, but it was a very different sensation and result. Dual-phase hurt far far worse; but both have the "tingle" of the AC voltage change, unlike the DC.
 
99t4 said:
I would have thought residential power-caused fire as the main danger and cause of death from residential power. No?
That could be the case, but it could happen with any type of home power. For direct contact though, surely almost all deaths would be from cardiac arrest. Therefor greatly reducing that possibility would be a big safety improvement.

[youtube]snk3C4m44SY[/youtube]

I'm not quite sure what to think about a safe DC voltage. @amberwolf and others have said they had trouble letting go or felt pain at somewhere under 60v DC, while others say they can barely feel anything. Then there's this video (time = 2:24) where the man touches 170v DC and says he can barely feel anything.

There's really no useable voltage for home power that totally eliminates the possibility of danger in every possible situation. I think choosing a voltage that's safe and virtually painless in normal conditions (dry hands) would be a huge improvement. Hopefully remaining non-lethal in all but the worst imaginable situations, with things like sweaty hands just causing pain. Maybe that's 100v DC, maybe somewhat lower, but it seems in the ballpark.
 
Everything here is trying to gain efficiency by inches and can be obliviated by distance of a DC part to it's source. I'd want to see changes to the "blade" style connectors we use, where you can partially pull them from the wall and still short something thin like a wire or piece of paper across the contacts than something like this. As Amberwolf said, DC can be far more dangerous- it's only incapable of starting fires or injuring someone at 24-30 volts.

THAT BEING SAID... assuming we had a method of happily running a DC system alongside our AC system without too much increase in cost, a 48 volt system could arguably be a good addition in a home for LED lighting and your fridge, if a 48 Volt fridge would ever be built. You arguably then could easily tie some battery backup system into it since you already have some kind of inverter/rectifier system. But part of that is my goal of having collections of 48 volt ebike batteries powering everything in my life as some kind of modular stack :lol:
 
Username1 said:
In my opinion home electrical should be ba...
If it costs a little more in copper, switches and breakers so be

Due to being much safer, electrical work could probably be done without a licen

You must be young to think you can design a better system than the one that is well over 100 years old. The builders of this ( GRID) knew well what they do, and will do in the future.

You will not change any system, and do, disregard many things, that I see. I have a negligible knowledge of electricity, but I know it will kill you quickly, if you know not, what you do.

I have seen the power industry, operate, and be designed for, for upward of 42 years, for my father built it and wrote the books. I have seen the resident zone, ... , I have seen the factory zone,..., I have seen the commercial zone.. I have seen the coal plant, the nuclear plant, the natural gas plant, the Methane digested plant, the water plant, the wind plant, the solar plant, built.

My father currently works on two nuclear plants, one for Mitsubishi in Japan, and one, the ITER fusion reactor, for Washington Group international, in France.

It is ALL about the price of copper. PERIOD.

Some nations have copper, some nations must pay for copper. There is only so much copper, to be had in the world. For some, or any, nation.

Choices to be made, compromises to be had.
 
When copper... vaporizes... it suddenly expands by a factor of 67,000 in volume.

Username1 said:
Maybe that's 100v DC, maybe somewhat lower, but it seems in the ballpark.

YOU are CRAZY for considering the contact of 100v DC. Life threatening. Certainly.


CONSIDERABLE SHOUTING said:
it's only incapable of starting fires or injuring someone at 24-30 volts.

THAT BEING SAID...

I can kill you in an instant with a little copper, a little current, and 24v DC. Start fires. No problem.

24v DC,... is certainly: considered " High Voltage" by some of the standards we use, certainly.


Username1 said:
In my opinion home electrical should be based primarily around human safety and simplicity of installation. There's a very narrow sweet spot where this is possible, somewhere around 100v DC. Going much higher in voltage you lose the safety, while going much lower you lose sufficient power (with reasonably sized wires).

In my opinion, we should use standardized code that places the commodity ( house, home) design and installations, in the hands of a professional, licensed to do this work through certified training, with an independent inspector for meeting the code as written: So as to be readily insured, by and readily replaced should that insurance be needed. Liability, longevity, cost, and reliability is all considered for you already.

Also, 16kW is nothing for an electric car charge rate.. We will need more. Typical home panel in the USA provides 2x that much power easily... And above that level? .../ you need special contract, and a special transformer, to make the power company happy: Ie not affect the neighbor power on the same line transformer.

It was all written in the standards by very educated people who know what they do. Yes, it is revised almost every year,.. but.. the knowledge was hard written the core, in the applications, that gained the experience, over the last 100 years of having readily available electricity for household use.

I think it is a pretty good system.

I can, sure as hell, feel my 72v DC battery, on dry hands, passing current... Dangerous... and... at even less voltage level. I will for sure make precaution from my battery, and the " live" lines. I am certain it can kill you in an instant.

Power is power.. and.. Potential is potential. Category-4 arc-flash protection, is similar to a bomb suit.


I have seen the Arc Flash. Dont F with it.

https://en.wikipedia.org/wiki/Arc_flash

https://www.google.com/search?q=Arc+Flash&client=firefox-b-1-d&sxsrf=ALiCzsZBtzE8YDStB8GRcqyYkPankPzLoQ:1651939719778&tbm=isch&source=iu&ictx=1&vet=1&fir=vSXqgj4I83ab2M%252CqpPZrnLJ4BTg4M%252C%252Fm%252F02vkgfn%253Br_ddbSqojy1WHM%252CTEV0_4nfanfaEM%252C_%253Bl-2GN6HEmiQrOM%252CgCGPV61FECuzGM%252C_%253B0ymSfwaU6PmuOM%252CSL5Z6TVO_-na8M%252C_&usg=AI4_-kQ-aWwX_5bSRXmvs2Ax4GkuZJ5gOA&sa=X&ved=2ahUKEwis8L-B4833AhWrQTABHQSBDmQQ_B16BAhWEAE#imgrc=vSXqgj4I83ab2M
 

Attachments

  • arc-flash-boundary.jpg
    arc-flash-boundary.jpg
    70 KB · Views: 1,230
Username1 said:
-------------------------------------

Receptacles
Receptacles (and breakers) would be labeled by their continuous power rating, instead of the non-continuous amp rating used now.

They are rated for continuous duty.

Every insurable UL tested NEC code adhering household receptacle or breaker that I have ever seen and or installed. Just like a fuse is rated for continuous duty, breakers and receptacles are too. If it says " 20A" on it, it will do 20A continuously. Fuse, breaker, or receptacle, until the end of time, installed as designed.

Absolutely. 100%.

Perhaps I am thinking of something you are not..... Miscommunication? I do not understand why one would think this is so? We have built a few houses that have been inspected. Designed a few power plants too. I have never seen a household receptacle that does not rate at its 100% duty cycle.


Please, read this book and come back to us with your ideas. Addresses many concerns.

First published in 1897.

https://en.wikipedia.org/wiki/National_Electrical_Code

https://www.amazon.com/National-Electrical-Code-2020-Quick/dp/B09SKJ9SXB/ref=asc_df_B09SKJ9SXB/?tag=hyprod-20&linkCode=df0&hvadid=564786910307&hvpos=&hvnetw=g&hvrand=3085438841664827561&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9007417&hvtargid=pla-1640863851963&psc=1
 
Ive seen 12V DC used in outdoor applications where moisture is a concern along with electrocution prevention (in spite of water-proofing efforts) such as underwater swimming pool lights. But of course as the watt demand goes up, the copper wire gets thicker fast.

Ive seen a few applications where 24V DC was used due to the length of the system, such as sailboats with a solar panel for back-up power.
 
DogDipstick said:
YOU are CRAZY for considering the contact of 100v DC. Life threatening. Certainly.

It's not about contacting it on purpose, it's about when it happens by accident. Ask any electrician and most will tell you they've been shocked multiple times by 120v AC. So if you don't like 100v DC which is much safer, you must hate the current 120v/240v AC standard.

DogDipstick said:
In my opinion, we should use standardized code that places the commodity ( house, home) design and installations, in the hands of a professional, licensed to do this work through certified training, with an independent inspector for meeting the code as written: So as to be readily insured, by and readily replaced should that insurance be needed. Liability, longevity, cost, and reliability is all considered for you already.

That's nice but electricians are a highly trained and expensive trade. If the voltage is low and safe enough, you simply don't need to deal the the added cost and bureaucracy. That's not just my opinion, the government already allows this under 50v. I also agree that work should be inspected, regardless of who installs it.

DogDipstick said:
Also, 16kW is nothing for an electric car charge rate.. We will need more. Typical home panel in the USA provides 2x that much power easily... And above that level? .../ you need special contract, and a special transformer, to make the power company happy: Ie not affect the neighbor power on the same line transformer.

Well that's 4 kW more than even the most powerful receptacle today, so again you must not be satisfied the current standard. That also doesn't mean you couldn't hardwire a more powerful connection, 16 kW is just the highest powered receptacle in my suggestion.

DogDipstick said:
They are rated for continuous duty.

So why does code state that continuous loads can only be 80% of the amp rating?

Having to look at different voltages, amps, then multiplying them to determine the power level, then having to subtract 20% for continuous use... There's no way most average people will ever understand this. That's why I suggest a single voltage, and labeling circuits by their continuous power level. Any average person could understand; this is a 1 kW receptacle, it always provides 1 kW of power.
 
For the people saying 100v DC is still quite dangerous, maybe you're right. Does anyone here think 48v DC would be low enough to be considered safe when accidental contact happens? Of course wiring a house exclusively for 48v would use much more copper than currently, maybe prohibitively so.
 
Higher voltage takes less resistance of insulation to skip over.
Just a general rule some people post about safe/unsafe 100vdc
Other reasons to, you start getting into specialy mosfets 100vdc+, more circuitry to handle blah blah blah I got no clue, google.
Doesnt really matter if you got a cut and it arches, will do it on 9vdc battery to tongue and what is that current, its had to be researched. Not much current at all, milliamperes I'd bet and its online you can check that out, but now imagine 100vdc, steel bike, steel handbar, steel seat post, steal seat rails, steel is conductive. I bet alum is conductive, look google is your friend, or frenemy

Username1 said:
For the people saying 100v DC is still quite dangerous, maybe you're right. Does anyone here think 48v DC would be low enough to be considered safe when accidental contact happens? Of course wiring a house exclusively for 48v would use much more copper than currently, maybe prohibitively so.
 
Username1 said:
So why does code state that continuous loads can only be 80% of the amp rating?

Show me. Cite a notation: a reference. Your source, so we are on the same page, please. I might be able to explain your misinterpretation. Based on your rudimentary experience in the application under discussion I see you are missing some certain knowledge on the subject.


calab said:


You can make one HELL of a taser with a 9v battery.
Lol.
 
Back
Top