Mind bending problem

US homes are fed with 120V for the wall sockets and lighting plus 240V for heavy loads like washing machines and tumble dryers. This is achieved by the utility company's local step down transformer having a centre-tapped secondary winding.

Load -B and Load-c represent different houses in the street. They use different
phases to balance the loads on the transformer.

Here we have a triphasic system with 220 between L1, L2 or L3 and N, and 380 (220·sqrt(3)) between 2 L's (a detail important only to small or medium businesses that have triphasic electricity and appliances, the bigger industries get higher voltage; if all the loads were triphasic the flow of energy would be constant with no 50 Hz oscillation, when the loads are monophasic this is met approximately, you need minimum 3 phases to ahieve this). The houses and flats get one L and the N as poles. The ground is totally independent. From each "pica" (a metal buried enough to find humidity) a tree of grounds reaches each house or flat outlet along with the 2 poles (the L and N). Connecting the ground to any pole (L or N doesn't matter) will trip the "differential", a circuit breaker that detects that both poles are carrying different amperages (usually a small difference) b/c the rest of one is being diverted to ground. This happens if any of the poles touches the ground wire, connected to the metal chassis of fridges, washing machines, etc (you only have to plug the defective and dangerous appliance to get the differential tripped, and you cannot connect it again until you unplug the appliance). In the diagram above Load-B and Load-C have two wires of "nearly" the same thing apparently but I'm not expert enough to say why this is so.

@JLArranz

Where do you live?

I think I've go red out.....but my assumption is not really logical.....

I took another Win11 pc over....onoe that I had just built...brand new......and it did NOT work at the socket in her computer office....
Plugged it into the one grounded socket in the kitchen and everything works as it's supposed to.....

1. Used my Fluke and determined I had a measured 117v at the socked...
2. I took the wall socket apart in the office to confirm there was no grjound wire......there is not.....
3. Went into the basement and pulled the cover off the breaker box.....I shut off/on each breaker until I found the breaker that is in the office....
The breaker is tight and no looseness in the breaker...
4. The lady told me that the grounded line to the office and to the kitchen were put in about 10 years ago.....
The house was built in the mid '50's...
5. Since she has only outlet in the house that are grounded.....the kitchen......I could not try any other outlets as they all were ungrounded duplex's...

So...since this issue was NOT apparrant with her older win 10 pc...which I has set her up with about 6 years ago......and it IS apparrant with the win 11 pc....
My assumption is.......Windows 11 has a "sensitivity" to ungrounded outlets....in my mind this really is not logical....but it seems to be the case.....
This is only one example.....and I would be interested if anyone else has run into this problem......

So my client is going to have an electrician come in and install a grounded outlet.....when that is installed I will go back and make certain that
everything is working as it should.....

Many thanks to everyone for all you help and suggestions.....

It's not a problem with windows or the hardware if you can plug it in anywhere else and it boots normally. Could be a fried outlet, a loose connection, a bad wire or any of a dozen other reasons, but regardless, probably better handled by an electrician.

kelper said:

@JLArranz

Where do you live?

Click to expand...

Spain.

@stevem5000 Years ago I had an outlet w/o electricity at all, although the connections were okay. There were other repairs and updates needed (I could do some myself, others not) plus an Ethernet cable (Wifi could do it but I preferred a cable) so I called an electrician. In the said outlet he replaced a chunk of embedded cable. No problems since. A cable that doesn't connect w/o apparent reason (in general for oldness or bad quality) is called here a "falsing" cable. Months before and not related I had installed myself a double outlet (for the coffe maker plus one free for tools etc) and I found it difficult for the little margin I had with the embedded cables length and room available inside the wall, it was easy to pull a cable too much and damage it internally.

The bulb I spoke about in my first post of this thread (intermittent connection due to internal failure, nothing about mains) may stutter at different paces or not at all (or maybe once per several seconds or a minute, twice in half an hour,... always on average) it depends on how much tight do I thread it and I believe temperature or random factors. Yesterday I used it and I thought: with this a computer would turn on or maybe not, and POST or maybe not, depending on the PSU and whatever else.

kelper said:

washing machines

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I've never seen a 240v washer. I'm going to guess that they must be either industrial washers or washers made for other countries.

stevem5000 said:

My assumption is.......Windows 11 has a "sensitivity" to ungrounded outlets....in my mind this really is not logical.

Click to expand...

I doubt that very much. I use to use computers in my shed that didn't have the ground wire. They worked OK. That is until I had a power surge and the surge protector couldn't protect my computer. It was my fault because I was being to cheap to buy an extension cord with a ground connection. At the time I was using a mini-PC. luckily it only cost me the price of buying new memory for the mini PC.

kelper said:

US homes are fed with 120V for the wall sockets and lighting plus 240V for heavy loads like washing machines and tumble dryers. This is achieved by the utility company's local step down transformer having a centre-tapped secondary winding.
View attachment 153161
Load -B and Load-c represent different houses in the street. They use different
phases to balance the loads on the transformer.

Click to expand...

I've been doing a little more studying of your diagram. It shows Load-A not using the neutral line. Wouldn't that cause a power spike and toast the house wiring and anything plugged in to the outlets?

Winuser said:

I've been doing a little more studying of your diagram. It shows Load-A not using the neutral line. Wouldn't that cause a power spike and toast the house wiring and anything plugged in to the outlets?

Click to expand...

No.

kelper said:

No.

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That's not what the lineman from the electric company told me when he had to reconnect the main power lines from the pole to my house. We had a loose connection on one of the 120 volt lines that was causing everything connected to that side to flicker on and off. He said that we would of had a serious spike if it had been the neutral line.

Winuser said:

That's not what the lineman from the electric company told me when he had to reconnect the main power lines from the pole to my house. We had a loose connection on one of the 120 volt lines that was causing everything connected to that side to flicker on and off. He said that we would of had a serious spike if it had been the neutral line.

Click to expand...

If you look at your Power Panel or Fuse Box, you will see that the neutral and ground connect to the same point.

Josey Wales said:

If you look at your Power Panel or Fuse Box, you will see that the neutral and ground connect to the same point.

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Yes this is correct except that the neutral wire feeds back to the power source. The ground wire is connected to a rod or pipe in the ground. AC power alternates back and forth so the neutral wire is a must. I'm not an electrician but that's the basics of how it was explained to me. As for the possibility of a power spike because of not having a neutral wire connected is what the lineman from the electric company told me.

Winuser said:

Yes this correct except that the neutral wire feeds back to the power source. The ground wire is connected to a rod or pipe in the ground. AC power alternates back and forth so the neutral wire is a must. I'm not an electrician but that's the basics of how it was explained to me. As for the possibility of a power spike because of not having a neutral wire connected is what the lineman from the electric company told me.

Click to expand...

Yes I know this, we have an 8 ft ground rod, the neutral is required , the ground and neutral in the box go to separate bars , but they are connected. Back in time all there was was a hot and ground, basically a 2 wire connection with round screw in glass fuses. Part of my last job was working with high voltage Rectifiers and I was certified on that . It alternates in sort of a sine wave which is why it is referred to as AC and not DC (direct curent).

Josey Wales said:

Yes I know this, we have an 8 ft ground rod, the neutral is required , the ground and neutral in the box go to separate bars , but they are connected. Back in time all there was was a hot and ground, basically a 2 wire connection with round screw in glass fuses. Part of my last job was working with high voltage Rectifiers and I was certified on that . It alternates in sort of a sine wave which is why it is referred to as AC and not DC (direct curent).

Click to expand...

I remember when my grandparents farm house had the single wiring with the porcelain insulators.

We used to see a lot of problems when I was a bench tech repairing TV's and VCR's caused by utility companies accidently cutting through neutrals on the three phase supplies in the road.

What happens next depends on the loading on each phase at the time. The UK's nominally 230/240 volt set up could see up to 400 volt supplied to a property but it would depend on the impedance of the loads on the other phases (other properties) as to what voltage a particular phase would move to.

kelper said:

US homes are fed with 120V for the wall sockets and lighting plus 240V for heavy loads like washing machines and tumble dryers. This is achieved by the utility company's local step down transformer having a centre-tapped secondary winding.
View attachment 153161
Load -B and Load-c represent different houses in the street. They use different
phases to balance the loads on the transformer.

Click to expand...

Mooly said:

We used to see a lot of problems when I was a bench tech repairing TV's and VCR's caused by utility companies accidently cutting through neutrals on the three phase supplies in the road.

What happens next depends on the loading on each phase at the time. The UK's nominally 230/240 volt set up could see up to 400 volt supplied to a property but it would depend on the impedance of the loads on the other phases (other properties) as to what voltage a particular phase would move to.

Click to expand...

The bulk of the National Grid runs at very high voltages 400 kV as this minimises power losses over distance.
This is stepped down to 220V (used to be 240V) for domestic users and 400V for larger commercial users.

Smaller premises e.g. a local shop would predominantly still use 240V.

As far as I know, no domestic users use more than 220V, and all domestic users are rated for 220-240V (50HZ). All UK domestic users have sockets with an earth except for small double insulated sockets e.g. shaver sockets in bathrooms. Also most of our three pin plus have a separate fuse. It is debatable if this is really needed now with modern central trip switches rather than central fuseboxes

Western Europe has a number of different standards but most (all) are also 220V-240V (50 HZ).

Denmark (where I lived) had a mish mash of domestic sockets - some older houses do not have earthed sockets, and often appliance plugs only had two pins. Technically, any UK applicance needing a earth could not be safely used on the older two pin sockets.

Fortunately, my Danish property had newer three pin sockets with earth and I was able to use my UK appliances. Many appliances on sale in Jutland (which borders Germany) were German imports with three German style pins, and you had to buy German to Danish 3 pin adapters (as the sockets were similar but not identical). I also used to use fused uk extension leads, changing the extension lead plug only as I was never quite comfortable not having local fused plugs with fuse ratings suitable for appropriate appliance.

Winuser said:

I remember when my grandparents farm house had the single wiring with the porcelain insulators.

Click to expand...

Yep, I saw them a lot as youngster in the '50's. Always warned by any nearby adults not to touch or mess with any of the wires wires, only touch the switches.

cereberus said:

The bulk of the National Grid runs at very high voltages 400 kV as this minimises power losses over distance.

Click to expand...

As I understand it, the higher voltage also allows for the supply wires on the utility poles to be of smaller gauge.