Reeading on Easter Morning

[Kellemora]

I hear ya, yes it is confusing. Since you understand DC, think of it like a battery.
The power generating station is the Anode, and planet earth is the Cathode or Negative Terminal.
Now a battery supplies continuous power, but a generator only sends out a signal like the magneto on a lawnmower, one pulse each time the magnets pass the coil.
OK, the generating station is essentially the magnet passing the coil 60 times per second or at 3600 rpm.
They can double the voltage at 180 degrees out of phase by added a second coil on the other side of the flywheel.

Electricians I used to work with, would put their thumb over a live wire, and then reach over and touch me.
They never got shocked, and I did even though I had very thick rubber soles on my boots.
Your friend was very lucky to be alive and unscathed. I would venture to guess it was his right arm and leg that the current traveled through, but he was essentially not grounded per se, but enough humidity in the air for it to arc to ground. I'm sure he had some burns on his hand and foot from the experience. Glad he was not killed though.
When I got zapped, it burned the soles of both of my feet, and welded my teeth together. My right hand was blistered, but not very bad, not like the bottoms of my feet.

When I had my UPS up and running, I never used the shut-down program, nor did I connect a USB cable to it.
I save all of my work as I finish each project, and then save everything to a backup.
If I happened to be working on something when the power went out, it gave me enough time to save what I was doing and shut down the computer manually. With a Monitor, External HD, and USB hub all connected to it, along with the computer, I only had about 3 minutes in which to save what I was working on.
I quit using it when it decided to recycle causing the computer to shut down, because it takes me about a half hour to get everything back up and running again.
For example: In my workspaces, I have 8 programs running at all times, not counting whatever other program I'm using at the time. Four of these are text files I copy and paste from several times a day, and the other three are running programs using terminal functions I cause to jump into action when I press F-keys assigned to them. They are programmed to handle the repetitive things I do many times a day.
To load these terminal programs, I have to make changes to their .config file to load each one, so they know which F-key to use, and then after the program is loaded, I have to load my file of instructions for what it is to do.
After I load and set up the last one, I always go back to the .config file and reset it so it loads the first instance properly.
Then make a change to load the second instance, then a change to load the third instance, then a change to reset it back for when it loads the first instance the next time.
I have 103 people I go do the same repetitive thing each day, that requires 6 things for each of them.
Or 618 steps I have to do. I can automate those steps so I only hit an F-key once, then sit back for 20 minutes while the computer does the work. But not exactly, I have to watch for a manual change that it may need and do that.
Without automation, it would take well over an hour and a half to do the same things.

[yogi]

Understanding AC isn't really like rocket science. I understand the role played by Mother Earth, but there is a logic module in my brain that refuses to accept the claim all electricians make. The way AC is generated involves two poles from the source and the load is connected across those poles. It's all metal conductors, just as it is in DC. The fact that you can tie a pole to earth ground and use that as a way to complete the circuit is outrageous. Dirt has A LOT of resistance and should not intrinsically be a very good conductor. That's the roadblock to my understanding of AC. There is no analogy in the DC world. There you need metal both coming and going. LOL

Now that you bring it up, my cousin's husband did have some burns after his encounter with the 440 AC. That's the reason they took him to the ER. I don't believe they kept him. Thy just patched up the wounds and he was on his way. You are correct about the zap involving his right hand. He was not a South Paw as I recall. While he was very fortunate, to say the least, there are stories about just the opposite occurring. I recall reading about a fellow who thought he would be funny and wired his ears to one of those small 9 VDC radio batteries. He died from his own stupidity, but there too I'd not expect the human skull to be very conductive, especially not for DC. It all has to to with chemistry. We are all just a sack of chemicals. Some are better conductors of electricity than others, I guess.

One of the cool features about this gaming keyboard I am using is it's ability to have multiple profiles. This is intended for different people using the same keyboard but also having different preferences for how to use the color schemes, actions, and macros. One of the things that can easily be done is key bindings. Each profile can have different bindings so that when you press F1 in the first profile you will get a different result when you press F1 using the second profile. Also, I have only a very vague notion of what you are doing there with all those programs. It seems awkward, to put it nicely, to have to edit a config file each time you want to do something different. Be that as it may, there are macros that can do exactly that. This keyboard will record your keystrokes and store them as a macro. I'm not sure how many macros you can store, but I know there are keyboards which can save dozens. I'm thinking that you could cut down some the the preliminary setup tasks if you could use macros to do it.

Also, Windows has a sleep mode and a hibernate mode. I'm pretty sure Linux does as well. The state of your desktop, and other processes, is held in suspension when you go into the sleep mode. Should you decide to hibernate instead, those states are stored to disk. If a power failure occurs during sleep, all is lost. But if it happens during hibernation, the it's all recalled from disk. You would think that's a great thing, and it is when it works. Unfortunately hibernation has not worked on a Windows OS since the days of XP. Sleep does work about 94% of the time. There have been times when I could not wake up from sleep, or when everything wakes up but the monitor. It's frustrating when that happens. It's because of the erratic waking process in Windows that I have not attempted to set up the automatic shutdown in the UPS. Maybe, someday, if by an odd chance I happen to be using Linux instead of Windows, I may try it to see what happens.

[Kellemora]

Well, technically, you have a Neutral, and an Earth Ground for safety reasons. But Neutral is still an earth ground.
There is enough Iron in the earths crust that it does make a good conductor, if you are down around 8 feet below the surface that is where it is a positive ground for sure. The earths magnetics also plays a role in how electricity flows
Again, think of a cars battery, the Cathode goes to the cars Chassis, and all the ground terminals from the devices in the car go to the cars chassis. Not much different than using the iron in the earth like a chassis.

Or as the aliens call us, ugly bags of water, hi hi.
Don't know what that guy was thinking, running a current through his head like that.
You can get by touching your tongue to a 9 volt battery, for a second, but longer than that will do damage.
A part of our heart does extend to the right of the sternum, but a shock on the left hand does go through the heart, while one on the right hand often just misses the heart, even if it comes out both feet.
One of Debi's cousins was killed when an arc from a high tension line jumped over 2 feet to hit him while working on the lines.

Sounds like a cool keyboard.
The program I use does allow you to save the macro's under a name for each one.
But I'm running three separate instances of the same program.
And each instance uses the same config file name which I cannot change, because it is internal to the program itself.
I don't think the designer of the program intended for folks to use more than one instance of the program.
But you know me, I try things to see if they will work. In this case it did.
But when I reboot the computer, I have to reload each instance and it's associated macro I wrote.
It automatically loads into F-5, then once loaded you select the macro you want to run.
Then I go to the config file and chance the F-5 to F-6 and load another instance, and load it's macro I wrote.
Then I repeat for F-8, and after I'm done I change it back to F-5 so it is ready for the next new bootup.
It only reads the config file when loading the program.

Although I use sleep, I don't recall ever using hibernate, not even on my laptops or netbooks.
I have all of my monitors set to go to screensaver after 10 minutes, and monitor to sleep after 30 minutes.
When I had the hard drive idle down option, I used to set it for 15 minutes also. Now it seems a HD will idle down on it's own after so many minutes, at least the external drives. I imagine the internal drives run constantly, unless they go to sleep with the monitor setting, hi hi.
Then again, maybe not, because I had cron jobs running to do an RSync backup from one external to another at 3 am which is still running and still works just fine.

[yogi]

Again, think of a cars battery, the Cathode goes to the cars Chassis, and all the ground terminals from the devices in the car go to the cars chassis. Not much different than using the iron in the earth like a chassis.

I don't know about iron in the earth around here; it's all Clay CIty. Then again, I didn't have a feel for the exact electrical resistance of Mother Earth so I looked it up: https://www.engineeringtoolbox.com/soil ... _1865.html

I must say that I was a bit surprised at the low numbers, even for granite. The clay around here, according to the chart, has a resistance of 100-200 ohms. A car chases, made of steel, has something closer to one (1) ohm depending on the length of the current path. That's one thing I didn't find in the table I cited. The resistance is stated but is one linear foot of soil the same as 1000 linear feet? I doubt it. It builds up in the car chases too but the grounding resistance there is insignificant compare to earth ground.

Since you brought it up, the "neutral" wire is another bit of black magic, but that one makes more sense than does Earth Ground. AC current flows in two directions and is plotted out as a sine wave. That zero crossing point from positive to negative is ... neutral, or at zero potential. That is the reason for requiring three wires. If only two wires were used the voltage swings would be from full positive to full negative, or twice the peak value which is 170 volts positive down to 170 volts negative, or 340 volts peak to peak. Of course that is instantaneous and not the (RMS) average value which we measure on a voltmeter. Thus, in my mind, neutral wires make sense as a means of keeping the voltage within a reasonable range.

Way back in the Windows Vista Era I tried to make my computer hibernate instead of shutting it down completely. It actually worked a few times, but did not work more often. I don't recall exactly what the problem was with Vista but the consensus was that a design flaw existed in that version of software. Windows 7 worked better in the hibernation mode, but it too was reliably unreliable. I didn't want to use the sleep mode because I knew that relied on whatever was in RAM and a loss of power would wipe out anything stored there. However, when I tested out the sleep mode it awoke successfully way more often than did the hibernate mode. Now that I'm using SSD's instead of HHD's it might be OK to use hibernation again. The disk does not have to come up to speed in order to work with SSD.

At the moment there's a lot of thunder and lightning going on and some "Dangerous Thunderstorm" warnings being broadcast. It's possible I may be testing how well the UPS works today. I already know the glitches are being filtered. Hopefully I won't have to find out if the battery backup works.

[Kellemora]

In most places, an 8 foot ground rod is required, driven down into the ground for a good earth ground.
But in dryer areas of the country, they have to go down 10 to 12 feet and sometimes lower for a good earth ground.

I don't think the resistance of a ground rod to the ground is all that important, since most grounded AC circuits are comprised of several grounding sources, not just the ground rod at your house. The incoming neutral wire is grounded also at the utility pole, and at every substation, and sometimes many utility poles en route to your house.
Your panel box is usually grounded the case to a copper water pipe and to an earth ground, and then the neutral buss is also grounded to earth ground.
I think what confuses a lot of folks is they are looking at a sine wave of HOT line, which switches between positive and negative on that single wire. Neutral is called neutral because it is at 0 volts to ground, so does not have a sine wave.
Now in an application, where you close a circuit such as running a light bulb, in that case the Neutral is an integral part of the Hot wire until it reaches ground potential. So even though the wire is called Neutral, it still carries the AC current, and as such the sine wave through it to an earth ground.

By a three wire system, are you meaning two 110 volt lines and one Neutral?
Or do you meant a single 110 volt line, a Neutral, and a secondary Ground line?
For all practical purposes, the Neutral is a Ground wire.

One of the reasons I never used Hibernate is because if you do Hibernate it is supposed to save everything you have running to the HD, and then when you come out of Hibernation, it will restore everything that was running back to the way it was before. That sounds good until you try to do it, hi hi. Some programs have to be fully loaded before the files they are reading can be accessed. So if it is not fully running, and the files it was reading are brought in from Hibernation ahead of the programs capability to handle them. POOF Crash Burn, hi hi.
Sleep, as far as I know, only has to do with the monitor going off, and in some cases the hard drive spinning down, but the computer itself is still running as normal.

Well, I hope your thunderboomers don't put your UPS to the test, although it would be good to know.
The time I lost everything was when a lighting bolt hit the CAT5 leading from the garage to the house.
It fried nearly everything that time. A UPS wouldn't have helped in that situation!

We have these strange types of fuses on our utility poles here. A power surge that should blow out the fuses, don't actually blow out the fuses, it only causes them to swing down like a door hinge. Then the utility company comes by with a bucket truck and stops to close each one that is open. I've never seen them replace a fuse, just swing it back closed again. So I guess they must work like a circuit breaker in a way. But I do think they are there more to protect their transformers than the customers they serve.

[yogi]

I don't know about Missouri, but up in Illinois where I lived they had those "hinge switches" for circuit breakers on the power lines. In the suburb I lived in, those breakers were located inside the distribution transformer boxes. Thus, in order to reset one they had to flip open the box, jab at the breaker with a ten foot long fiberglass pole, and we were back in business again. It was a very simply fix, but it often took the crew an hour or more to get out to us. Then if there were a lot of power outages, it could have taken several hours to reset all those breakers. I often thought that it could be automated, and perhaps with the smart grids they are installing it is. The last outage we had here in O'Fallon only lasted 7-8 minutes. Then, too, most of the wires around here are underground.

No matter how you put it, both AC and DC need a complete circuit in order for the current to flow. It cannot be one way into the ground. The source that generates the current needs a return path in order for it to work. Otherwise all you have is lightning. The neutral wire is the return path, but the part I don't get is how Earth Ground can act as a return path as well. The generator is grounded to earth as are all the distribution points in the grid so that the earth itself is the return path. That copper rod going into the dirt is essentially zero resistance, but the moist soil follows the chart I linked to. This whole concept of earth conducting electricity is contrary because any amount of resistance generates heat and a loss of power. This loss can be and is incurred in the return path as well as on the load side. Because the variations in ground resistance are so great the loss of power should be substantial; but it's not, obviously. Thus, it's all Black Magic as far as I'm concerned.

And just for information purposes, my reference to a three wire AC circuit includes two source poles and one neutral. There is a positive source and a negative source at the generator and polarity is determined by the direction in which the current is flowing at any given moment. The neutral, as we both seem to agree, is at zero potential, or ground. Thus when you put one probe of the voltmeter on neutral and measure to either positive or negative source poles, you will read 120 Vrms, or the 170 Vpeak as seen on an oscilloscope. It's because of the neutral (earth ground?) that we have 120 Vac in our house wiring instead of 230 they like in Europe.


Hibernation in Windows stores the state of the computer on the hard drive. That takes time, of course, in terms of shutting down as well as coming back up to speed. Everything is written to disk in hibernation, including any open documents you might have on the desktop. Sleep doesn't save any data. It only saves the state of all the processes, and it does so in RAM instead of on the hard drive. Thus, when you hibernate, your computer basically shuts down entirely, or at least the OS that is hibernating does. Sleep, however, does not shut down the system entirely because it needs to keep RAM alive. My guess is Linux operates under the same rules but I seldom sleep and never hibernate in that environment. The monitor and screen savers are entirely different processes and are disabled in both sleep and hibernation modes.

[Kellemora]

Over in our ritzy area of Knoxville, they do have solenoid closures on the circuit breakers. Because of this, they are enclosed in a box like you mentioned your's were. But down here where I live they stand out in the open, bolted to the side of a utility pole.

You can power AC items without a return path, if you power them from two 110 volt lines out of phase with each other. No neutral required. But ground aka Neutral is not really a return path through the ground to the source. The ground is the end of the road for the AC signal. Think of it like RF! An antenna still transmits, even if there are no receivers to pick it up.
This is one thing Tesla was working on, the transmission of electrical power over the airwaves. Never perfected it though.

Hmm, I think Europe is 220 on a single line, 440 on an out of phase pair, and they run at 50 Hertz.
So using two out of phase 220 lines, they can get 440 the same way we get 220 out of two out of phase 110 lines.
It's just the way they designed their system. And technically, the voltage doesn't matter all that much as long as the devices are designed for that voltage. And of course electronics need to be geared to 50 cycles instead of 60.
This is one reason early European TVs had so much flicker to them, the flyback and width coils worked at 50 Hertz, so the raster sweep was also at 50 Hertz. Or to put it another way, it only drew 50 lines on the screen per second instead of 60 lines on the screen per second. So the human eye could pick up the flicker much easier, and it was more annoying too!

I have most of my computers set to screen save after 15 minutes, sleep after 30 minutes, hibernate Never!
The OS I'm using doesn't matter.
In the early days of computing, I would turn my computer off when I was not using it, and fire it back up in the morning, or if I needed to do something on it during my lunch hour. But the one I took to work with me, was never shut off, not even while we were closed, because I had it monitoring a couple of things throughout the night.

[yogi]

All I can add is that we certainly have two different understandings of how AC is designed to work. There is no such thing in the world of physics as a unipole source, which is what the hot line of AC sources is being described as. There are static discharges, such as lightning and feet shuffling across a wool rug, but even that has two fields at different charge levels.

RF and traditional AC power lines both have electro-magnetic components that are radiated. RF is, after all, AC. Because the electro-magnetic energy can be radiated it would be possible to transfer the inherent power without wires. This is in fact what happens when you receive a radio signal. The power at the transmitter is transferred over the air to your receiver where it is detected. However, most of the original power is lost to radiated energy which is why Tesla failed to come up with a viable scheme. Lasers, on the other hand, don't lose as much energy in the transmission process, and they have been used to send power down to earth from satellites. If they can make that method safe and efficient, it's probably how power will be distributed in the future.

I did the same as you back in the old days and simply shut down the power to my computer at the end of the day. The boot process was exceptionally long back then, plus all the programs I typically used had to be restarted each time. It wasn't a big deal for me because I was using the computer just for fun, but a complex operation such as what you are doing would be a pain in the drain to restart every single day. People kept telling me that it was dumb to shut down the computer all the time which is why I looked into sleep/hibernation. A complete shutdown might have been unnecessary, but it was a graceful way to exit and restart Windows. I could not say the same for sleep and hibernation. Eventually I came to the conclusion that hibernating Windows is just asking for trouble. I've not tried it in Windows 10 but might get around to testing it again since that system is on SSD. I still shut down the laptop every night, but the tower goes to sleep. I've been able to stabilize Windows 7 and make it work very efficiently which is the main reason I'm hesitant to migrate up to something else. If, and when, I get around to building a new tower, that box will have Windows 10 along side Windows 7. If a miracle of nature should transpire between now and then, it is possible for me to make my favorite Linux distribution the default boot OS. Then I can learn how to make computer operating systems work efficiently once again.

[Kellemora]

After working both as an electrician, and in electronics, I'm still confused on how a lot of things work.
Many years ago, I studied how electric was generated and transmitted over power lines, and why they need to use such high voltages, yet could do so on comparably small size wires. But whatever I learned about this has long since been forgotten.
I know I've seen electric arcing a good two feet at a substation one day not to long ago. And about a foot or more each time they have to open or close one of the transmission lines. Makes me not want to be anywhere near the place when they do that too.

Since the days of Tesla, they have come a long way with various means of transmitting electrical power without wires. Unfortunately the loss, and the reestablishment of current at the other end is so lossy, it could never be viable, at least not yet.
I've seen some amazing things with these newer super conductor magnets that might be one key to generating more electric at a lower cost, like at hydroelectric plants, where they have the weight of the water on their side.

I've not actually shut down a computer at night in more than two decades. Like you said, it is such a pain to get them all booted back up again, finding their place on the Network, and getting the programs I keep running all the time loaded and up and running.
I do know heating up and cooling down does more harm than letting them idle along at a moderate temperature.

Talked to a guy the other day, who's dad works for a company that makes solar films, which is supposed to be the upcoming new thing over solar panels. They use these nanocarbon chains to get much more power per sq. ft. than normal solar panels. But currently the cost of such is too high for commercial use, but they are getting it down a little bit every month.
I've also seen solar panels that look like normal roofs too, but again, they are super expensive yet.
And of course, film over glass windows that work like solar panels, but they are clear so can be used over windows. Might be great for large office buildings, and skyscrapers, some day.

[yogi]

Apparently the problem I have is that I do understand how AC is generated. Pass a magnetic field through a wire and current flows. Pass the opposite pole of the magnetic field through the same wire and the current flows in the opposite direction. It's that simple. It gets more complicated when you try to understand what exactly is current flow. A single length of wire open on both ends will not conduct current. That wire must be looped to provide a complete path for the current. My understanding of it all says Mother Earth is not a valid return path. Reality, however, demonstrates otherwise. LOL

It makes sense to reason that the expansion and contraction of electronic components resulting from natural heating and cooling of the circuits would stress the materials from which they are made. If that were truly the case, then modern CPU's would not last more than a few weeks. During their normal operation the temperatures swing dramatically depending on what is being processed. While I've experienced more than a few failures with all the computers I've owned, I can't say any of them failed due to heat stressed components. It is possibly to physically melt down the silicon and plastic as a result of thermal run away, but that isn't exactly normal operation. The way I use my computers allows for complete shutdowns and cold starts on a daily basis. Everything I need to get going can be done in under two minutes.

Nanocarbon alloys are amazing things. They have not yet found the full potential for such structures. I can easily understand how they would enhance the operation of solar cells, and the technology will do nothing but improve over the years. It could come down to electronic vehicles that don't require traditional charging stations, for example. Just a few hours in the sun might do it, and that can happen while you are driving which would extend the range of such cars dramatically. There is a claim that the state of Missouri will be more than happy to give me some good amount of money to install solar panels on my home, all in the interest of conservation. I doubt it would ever happen in my neighborhood. The HOA certainly has rules about that.


My daughter and her husband drove up from Florida this weekend. They are staying with us a few days prior to their departure to Wisconsin to visit with my son-in-law's parents. We spent much of the day at Stone Hill Winery in Hermann. There wasn't much of a crowd at the vineyards and very few people were wearing masks. We enjoyed some snacks picnic style out in the open air and then went into the German restaurant. It's a lovely place and I recall that you have been there too. The menu did offer some German style meals, but to be hones it didn't seem very genuine. I've been to other German cuisine restaurants up by Chicago where the atmosphere and menu was a bit more authentic. It all was enjoyable nonetheless. I don't get to see this daughter very often, but she is the one who lived in Clayton at one time and inspired us to look around here for retirement living. There is some talk about her hubby getting a job up north and them moving back to the Chicago area to be close to the airport and his parents. If that does happen, the irony would be brutal.

[Kellemora]

We had hundreds of lights in our greenhouses, some for the plants, and others in working areas.
Needless to say, the ones used over the plants were on timers to extend the daylength the plants needed.
But the ones in the working areas stayed on usually 24/7 in some areas.
Guess which lamps we had to replace most often?
The ones on all the time, thus using up their 1200 hour lifespan?
Or the ones that were only on for 3 to 4 hours a day?
The ones that burned out most often were the ones that were turned on and off.
Those left on 24/7 may last for well over 3600 hours or even 4800 hours.
Lights on dimmer switches always outlasted those on on/off switches too.
So, I'm thinking as far as computers go heating up and just cooling down to warm is better than cooling down to dead cold.

I've seen some of these newer carbon black that are so black it does not reflect light from it.
That's good as far as not reflecting our sunlight back into outer space, but bad in the fact the substrate gets much hotter.
But then carbon is already carbon, hi hi.

I hear ya! My son was living in Florida when I moved south, then he moved back to St. Louis again too.
Speaking of the devil, my son and my brother are here right now. They got here last night and will leave tomorrow morning.
And with that, I guess I should get off here and visit with them a spell.

[yogi]

The thermal dynamics of a tungsten filament in a light bulb is hardly the same as that of a silicon chip embedded into a block of plastic. The coefficient of expansion associated with the metal tungsten is very much different than that of silicon. Add to that the temperatures involved. That light bulb filament reaches a temperature of 4500F in order for it to glow the way it does. A CPU intensive game will raise the silicon temperature to 175F, maybe. Thus, even if the thermal expansion coefficients were identical, the filament temperature alone would be more destructive. Then, too, the filament is 2-3 mm in thickness but the silicon chip is a 600 mm square, typically. The bottom line here is that the tungsten expands and contracts in a far greater magnitude than can any silicon CPU chip. The stresses in that light bulb filament are extremely greater than anything AMD can produce.

While all the above is true, that does not invalidate what you observed in the greenhouse lighting scheme. It certainly would be best to keep the bulbs at a constant temperature so that the expansion and contraction stresses are minimized. And, for that matter, it would also be a great idea to keep the silicon chips at a constant temperature. However, the CPU's are by design way way way way stronger than tungsten light bulb filaments.

It's nice to have the kids close by, at least in theory. LOL We are kind of isolated here in Missouri, but for the most part we still consider that to be a plus for our lifestyle. Chicago is a 5 hour drive from here so that it would not be totally unreasonable if the kids both lived there. Florida is a two day drive and not likely to be a place we would drive to. We moved out of the Chicago area for a few reasons, and at this point in time I can't see any compelling reason to move back. Perhaps a move back to small town Illinois would be in order, but the big city is out of our price range now. We made our fortunes there and are grateful for that. It's just that I'm not in a position to give it all back to them over the next few years. The kids are more flexible and still working so that the cost of living isn't a big deal for them. We lived in the same area for 72 years, but my oldest daughter seems to move every other year, or more often. Due to the pandemic and all, it's been a while since we got together. I suppose I should get back to them before they leave tomorrow.

[ocelotl]

As far as I remember, the idea in generation and transmission of electricity is to avoid electrostatic discharge to physical ground, so the neutral of the generator, and of each side of each power transformer are grounded. Now, theory says that for all practical purposes, it is best to reference all measurements to physical ground. Only in certain circumstances, like in power supplies, the measurement equipment can be ungrounded and let to "float" to avoid damaging discharges between the reference plug and physical ground. Most designs use physical ground as a conductor, bu, as you already know, resistance of the different types of soils is not zero.

On incandescent lightning, the most stressing moment is the sudden temperature change when turning on or off the bulb. That's why repeated switching bite on the useful life of a bulb. Now, on most dimming circuits, even when the bulb is at 100% power, the design recommendations call for soft start and stop circuits, so that the bulb or motor is powered on and off gradually, so relieving the stress on it and improving the duration of the dimmed unit. Most ocmputer power supplies nowadays also have soft start and stop designs. The issue regards more on the side of loading/stopping all the software in use. Eventually every computer needs a soft reset (AKA a turn off/on cycle) since not always the different software processes are terminated and dismounted from RAM efficiently.

On fluorescent lightning, the limitation on the life of the bulb depends on the deterioration of the electrodes that ionize the gas inside the bulb. They are literally eaten away by the arc that forms at the turn on of the bulb, since to start, the ballast works as a self transformer that raises a spike at least 800 V between electrodes, where there is a discharge arc that heats and ionizes the gas inside the bulb. Once the ionization happens, the bulb internal resistance drops in a way that the voltage between the electrodes go down to an average of 250 to 400 VAC. Now, an addition to that is that an improvement to reduce somewhat the energy consumption is that in the bulbs that have four pins instead of two, the electrodes are small tungsten filaments, similar to those of incandescent lamps, the idea being that they are heated using a small part of the power, thus facilitating the ionizing arc formation.

I remember having read about translucid solar panels for about ten years, but costs so far have been prohibitive. Eventually, we will see commercial versions sooner than later. In my opinion, the issue is more in the side of energy storing and distribution. Most of the batteries have useful lifes ranging from three to five years, so that there's a need to develop longer lasting energy storing systems... By now I'm reading about fuel cell procedures. Wll update later.

[Kellemora]

In a couple of our greenhouses, we had string arrays of lights where the lamps were placed closer together. The reason for this was we were trying out 130 volt lamps instead of 120 volts lamps. They are slightly dimmer, so it took an extra lamp for every ten to make the same amount of lumens on the growing beds.
Adding the extra lights meant the cost more to run as far as electric goes, however, they only had to be replaced about half as often as 120 volt lamps, so the cost savings was in the bulbs.
At my cousin's greenhouse, after compact fluorescents came out, that is what he used. His electrical costs were lower than with incandescents, but they were so short lived all of them had to be replaced every six months or more often as individual ones burned out. They never got the 5 to 7 year promised lifespan from a single one, nor could they, because they lose spectrum ranges very fast. Basically, any greenhouse that uses fluorescents of any kind have to change them out every six month, while in an office setting they only change them out every other year, and then only half of them each time they change them out.

Old light bulbs always lasted longer than the new light bulbs, speaking of incandescent bulbs, because they didn't have the technology to make the filaments as fine. They all hard larger diameter filament wires, so they naturally lasted longer. Now they have it down to a science so they know exactly how long the average bulb will last.

Not so with fluorescent or LED lighting systems. Their power supplies usually go belly up fairly fast. And LEDs have many other problems, such as flickering due to faulty power supplies. And I do believe LED lamps can talk to each other too.
I have a three light fixture in my office. I can use one or two LED lamps in it, but if I add a third, they will flicker for a while, then all will go dim. I can replace any one of them with an incandescent, and then they will all work just fine.
That being said, I found another style of LED lamps that look like antique lamps. I have one fixture that uses 5 lamps, and another than uses 7 lamps, and if I use that type of LED lamp, I can use nothing but LED lamps. And so far, those more expensive ones are lasting a good long time. But nowhere near what they claim on the packages.
I think if they can advertise their lamps last for 7 years, then they should have to warranty them for 7 years!

For Ocelot, we used to have Panelscent night lights all through our house back home. They were small flat disks that glowed light blue, enough to see the path in the hallways. Plus I had a large 14 inch square one in the ceiling of the bathroom that we left on 24/7 also. They only cost about a penny a year to run, and the big one about 15 cents per year. We never had one burn out, but left them all in place when we moved south.

We have the technology today to have obsolescence built into nearly every product.

[yogi]

If I recall correctly those high priced LED's that claim a long life claim they can last "up to" seven years of normal usage. They don't guarantee it, of course, and if you read the fine print they explain what normal usage is. All I remember about that is none of my applications fit what they called normal. LOL

Juan's explanation of why AC generators are grounded makes sense. That always was the case in my mind. The theory is sensible. The fact that AC can "discharge" to ground and thus complete a circuit of current flow still doesn't make sense. I might concede to the wisdom of earth grounding if you are within a couple feet of the source, but beyond that the earth acts as an insulator, in theory, to my way of thinking.

We have the technology today to have obsolescence built into nearly every product.

That's been the case ever since the invention of capitalism with free and open markets. Maximizing profits for the shareholders is the name of the game.

[ocelotl]

Indeed in both compact florescent and in LED lamps the weakest point is the power supply. They design it so weak for each model that it just barely powers the fixture... Just a cent per supply would make them last double the time, but they don't do it because the money flow gets lower for them. In the bathroom I just use fridge incandescent lamps. Humidity there kills any power supply very fast... The fridge bulbs are made tougher so they can stand their promised 1000 hours in the fast cycling cold ambiance inside a fridge. In the bathroom they last 2500 to 3000 hours, as far as I have measured...

[Kellemora]

I hear ya on that time frame for lamps, hi hi.
Even so, the old antique lamps still lasted longer than the new lamps do!
Heck, when we took down a drop ceiling in my grandmothers old house, a light that was above the drop ceiling was on and burning. The lamp itself was probably from around 1917 to 1922 give or take. It was still burning in 1980 when we took down the drop ceiling. By then though you could just barely see the light from over 60 years of grunge and grime coating the bulb. And you don't want to know what the tops of those drop ceiling panels looked like, hi hi.

I don't know if I can explain the purpose of what are known as case grounds in a way that would make sense, since Neutral is also earth ground, but taking a different path, sorta.
Neutral is what the device needs to make the motor run or the lamp to light, after the hot wire is connected.
Simply because when a lamp is on, or the motor is running, Neutral is also Hot all the way back to the source.
That is why they are termed LINE and LOAD.
The Romex wire runs from the panel box out to the fixture, and has three wires in it. Hot, Neutral, and Ground.
But back at the panel box, the Neutral Buss bar is connected to earth ground.
So why the third Ground wire, which bypasses the Neutral Buss and goes straight to earth ground.
Well, let's say you are holding an electric drill in your hand with a metal housing.
Something inside breaks causing the hot wire to touch the metal housing.
This would make YOU the ground for the Hot wire, and we can't have that.
So the case is always a separate ground to earth ground to keep you from becoming the ground.
It took me years to understand the purpose of the extra ground, since they both (Neutral and Ground) go to earth ground.
But if you use the metal case of a device as Neutral, you can get shocked when the item is running.
You may remember touching the refrigerator at the same time as you touched the water faucet or another appliance and got a nasty shock. That was because decades ago, the case was grounded to the Neutral wire.

For Ocelot:
I've basically done the same thing in many applications. Bought appliance bulbs and/or 130 volt lamps. I bought a whole box of 75 watt bulbs designated for traffic control lighting many years ago. I had them in my outdoor fixtures until only recently when I replaced them all with LED lamps.
My son bought four large fluorescent globe lights for me a few years ago. Actually, he bought them for himself but didn't like how they worked. They start out dim and slowly get bright over time. So I said I would take them. They are known as Sunrise lamps. They are great for 3 am trips to the bathroom because they are dim when you turn them on, and you are done before they get much brighter, hi hi. I also have an LED nightlight in there in the ceiling that runs 24/7 if you don't want to turn on the other lights. It is the equivalent of a 7 to 9 watt bulb, but draws less than 1/8th watt, which was perfect for what I needed it for.
I have a 3 foot LED lamp that looks like a shop light. That thing puts out 4000 lumens and is daylight color range.
My brother replaced all of the long fluorescent lamps in his warehouse with 5000 lumen LED tube lamps. Said his electric bill dropped by over 1/3rd when he did that. But their is a downside too. If he uses less than so many KWH per month, his rate goes up from industrial to commercial rates.


I don't know Yogi, some companies take pride in the quality of their products.
I have two Emerson dorm fridges, one is 40 years old, the other 30 years old, they still run perfectly.
The window AC I had built into my office wall ran for over 14 years, and it was a discount model AC unit to start with.
The new one I have now probably won't make it to 3 or 5 years.
I know we've had to replace a couple of our brand new kitchen appliances already, the fridge and the dishwasher.
That ten year warranty on the fridge was useless, it only covers the compressor and nothing else.
What I hate most is the design of most new products is drastically sub-par.

[yogi]

AC_Circuit.jpg (24.87 KiB) Viewed 855 times

The above image represents my (mis?)understanding of Alternating Curren, AC.

Some device generates the AC current as explained elsewhere in this thread. The generator has two poles, one positive and one negative. All electric current, be it AC or DC, flows between the positive and negative poles. The load is placed in series or parallel with the flow of electric current. Thus the electric current generated by the device flows through the load and back to the generator. For the purpose of our discussion I labeled the positive pole hot and the negative pole neutral. The neutral wire is said to be grounded, and the connection to earth is on the same terminal as the neutral wire according to the above explanations.

I'm fairly certain the image represents what has been described in this thread, and is consistent with the physics of electric current flow.

I'm also told that the AC generator is grounded to earth, which makes sense for safety reasons. The part that does not make sense is that it is said the AC current will still flow if the neutral conductor is removed. That is to say the earth connection on the generator side acts as the return path from the load which is also earth grounded. However, earth (soil) has resistance. Any substantial distance separating the load from the source will increase that earth resistance dramatically. While the current from the AC generator is equal throughout the entire circuit of series loads, the source voltage is split among the loads in proportion to their resistance. That means the original load will see much less voltage than supplied at the source because the series earth resistance would cause a voltage drop of it's own based on it's inherent resistance. This is simple Ohms Law.

You can't just swap out a copper wire and substitute it with dirt and expect electric current to flow unimpeded. Well, that's the theory. Apparently something else is going on in practice.

[Kellemora]

You have it correct except for one minor thing.
Is that supposed to be a Ground symbol midway on your Neutral wire?
If so, it does not belong there.
Although Neutral is grounded, it is done so ONLY in the buss inside the panel box, lest you get stray voltage and current in the physical earth ground.

One other thing AC does not have a positive and negative pole like DC.
The Positive side is a sine wave that goes both above and below Zero, so it is the positive pole that is changing from positive to negative. What you have marked as negative is the return path to the generating circuit. That is if my memory serves me correctly.

Let's try this method. Power Station output is Line, but at the Meter on your house, since LINE is going to the Meter, the Meter is the Load. Line/Load is really confusing to many which is why a few use the terms upstream and downstream.
From your electrical outlet, the output side is called LOAD, but at the next outlet, the input side is called LINE, and the output side is called LOAD. So a wire running between two devices are fixtures is both LINE and LOAD at the same time, depending upon which end of the wire you are talking about, hi hi.
Normally, we call the wire providing the current LINE, and the wire leaving the device to power another device is also called LINE.
Even though the terminal itself is called LOAD, because it is going to power something else, or returning to ground via the Neutral wire.
Or another way of putting it, On a device, the side accepting the power is called LINE, because the LINE feeds it. The other side of the device that would got to neutral wire the terminal on the device is called LOAD.

In a DC circuit they are called Positive and Negative.
So, if you have ONE device in the circuit, the input side is Positive, and the other terminal is Negative.
But, what if you have TWO devices in Series?
You would take the power from the first devices Negative Terminal, to feed the Positive Terminal on the second device.
This then makes the Negative wire (Load) now the Positive wire (Line) to the next device, because (Load) shifts the output side of the second device.
Clear as MUD eh!

Hmm. Actually, if you test a Neutral wire with the LOAD on and running, you should only see about 1.5 to 3 volts on the Neutral wire to earth ground. While the actual ground wire to the case of the device should read Zero volts.
However, Current is something else entirely. Current flows throughout the entire circuit. But not on the actual earth ground.

[yogi]

It is obvious that we learned about electricity and electronics in two different schools.

First of all, there are two different ground symbols in my image. The one in the center of the neutral wire is the standard schematic symbol for chasis ground. The other one with three prongs is earth ground, or that rod you stick into the ground in order to meet the building codes. You have often expressed the idea that the earth ground seems superfluous, and when you look at the diagram I posted that would indeed be the case. All grounds go to the same place.

An AC power source requires two poles regardless of what term you use to describe them. In order to understand my reasoning for marking them positive (+) and negative (-) it is necessary to recall how the AC electromotive force (EMF) is generated. Keep in mind that the definition of EMF is simply "the difference in potential which allows for current flow." Imagine the (+) terminal to increase in voltage potential while the (-) terminal remains at zero. This difference will cause electrons to flow through the conductor. In practice this difference in potential is caused by coil windings passing through a magnetic field. Magnets, as you certainly recall, have two poles; one positive and one negative. When the AC generator coils pass through the positive magnetic field, the electrons flow in one direction and create a positive voltage at the (+) terminal. When the AC generator coils pass through the negative magnetic field the electrons flow in the opposite direction and create a negative voltage at the (-) terminal. An AC sine wave is what you see on an oscilloscope connected across the AC source terminals and is the result of the voltage potential changing polarity as the generator coils pass through positive and negative magnetic fields. All of this happens WITHOUT any grounding whatsoever.

Tying one of the generator poles to a chasis and calling it ground is simply a convenience. Current will not flow unless it has a return path to the generator, and chasis ground is said to be that return path. In house wiring there is no chases, so to speak, so that the return wire is called the neutral wire. Some confusion arises because the chasis is commonly (and incorrectly) called ground. The confusion is multiplied when you tie the chasis, the neutral wire, to a rod stuck in the earth and term that Earth Ground. The earth ground is a safety measure that you explained very well further up in this thread. Its purpose is to short circuit any current that a human might come into contact with when they touch the chasis. The current goes through the earth ground instead of through the human.

If you understand all that I wrote to this point, then we all agree on what is happening. However, my method of reasoning does not allow for the earth, dirt, soil, or anything but a low resistance conductor to pass current. Yet, AC obviously will cross over to earth ground which is contrary to all my instincts about electricity.


Regarding LINE and LOAD, the reasoning for such terminology is not that difficult to comprehend. The line side points to the source of the current and the load side points to the destination. Simple. The only time I've seen such terminology in electronics is when dealing with audio. The source of the audio is frequently referred to as a line, which corresponds to the source of AC in things such as house wiring. Loads are typically attached to power supplies, but certain other circuitry can also be loaded. Regardless of what you call it, electrons need a complete path to and from the source in order to flow. This is true for both AC and DC.


And, one last observation about the polarity of AC. It does indeed have a positive and and a negative pole. The difference between AC and DC is that the polarity remains constant in DC circuits, but it alternates in AC (i.e., alternating current). My diagram is an instantaneous representation of an AC moment. When the current is flowing in the opposite direction the polarity in my diagram is reversed. Keep in mind here the definition of EMF, that is to say, it is the difference in potential. Zero volts/current is the common reference point, but it does not have to be that way. The positive pole can be 9 volts while the negative pole can be 3 volts and current will still flow due to the difference in potential. I suspect that attaching a "ground" to AC circuitry was an attempt to standardize the voltage reference point. Things got complicated from there.