Is there any reason to support the idea that cables, interconnects or any other kind of wiring can be considered directional? It seems that the theory is that carrying current will alter the molecular structure of the wire. I can't find anything that supports this other than in the case of extreme temperature variation. Cryo seems to be a common treatment for wire nowadays. Extreme heat would do something as well, just nothing favorable. No idea if cryo treatment works but who knows. Back to the question, can using the wires in one direction or another actually affect it's performance? Thanks for any thoughts. I do abide by the arrows when I have them. I "mostly" follow directions but I have pondered over this one every time I hook up a pair.
That particular phenomenon (second paragraph in above article) has been accepted by Physicists, for decades
Almost a century, in fact! But quantum entanglement has no practical applicability to music reproduction today. It may in the next few years feature in a class of computing that is not based on binary logic, that may be useful for solving some problems.
It has never been demonstrated (to this point) that it can be used to communicate faster than the speed of light. To quote Wikipedia
I seem to recall that in another post you said you learnt your electricity from this forum? Could I suggest reading a couple of recognised textbooks? Also, science advances when researchers publish peer-reviewed papers in scientific periodicals, which other researchers can cite in their work, or can challenge. By all means, read widely but for goodness sake, don’t quote indiscriminately.
So you are saying in a closed circuit the signal flows back and forth from the source to the load. Correct?
Almost. The signal is the voltage, which is analogous to electrical pressure caused by a slight excess or deficit in the balance of protons and electrons. Apply a voltage to one end of a wire, and almost immediately (depending on inductance) the voltage becomes uniform along the wire, including at the far end. If you make the voltage oscillate at one end, it oscillates at the other end. You don’t even need a circuit, though there is an almost imperceptible average movement of electrons when the applied voltage changes.
There is a slight time delay, which Quad make use of in their electrostatic speakers. They want to simulate a point source of sound a foot behind the panel. If you imagine sound radiating from that point, it reaches the centre of the panel first. then radiates outwards in rings. Quad delays the voltage signal to concentric rings using 12 miles of wire wound into inductive coils.
If the source is a CDP and the load is an Integrated Amp, using only one channel, the signal leaves the output on the hot wire of an IC, flowing back and forth, flowing to the input of the Amp, through the input circuit of the preamp, and then returns on the return wire back to the CDP output... Correct?
Vaguely. The source is a CD Player, so it outputs a line-voltage analog signal at audio frequencies, say 20-Hz to 20-kHz. The peak to peak voltage swing is around 1 Volt. Your interconnect (to me, IC also means integrated circuit) looks like a two-wire with RCA connectors rather than a 3-wire balanced connection, so there is a circuit. The amplifier presents an impedance (usually very high) so provides a path for some current to flow. The current flows out on one wire and back on the other. When the voltage reverses, the current reverses. The amplifier and the player could be designed so the current is regarded as the signal but almost universally, voltage is used as the signal instead.
As for the current the "netmovement" of charge, it will measure the same on the hot wire as the return wire in the IC back to the analog output section of the CDP. Correct? This whole event takes place in the wires... Correct?
Correct. The current flows in the wires. This is not the whole event though! The current creates a magnetic field outside the wires. Changing magnetic fields create changing electrical fields - the foundation of electromagnetic waves. Note that these waves are not made of charged particles like electrons!
How does the input section in the preamp, for a better word, extract the signal from the IC as it travels through the closed circuit, flowing back and forth, back to the CDP? And what happens to the signal that returns back to the CDP?
Wow! Is that how you are saying it works?
The job of the amplifier is to take the AC input voltage signal (about 1-Volt maximum peak to peak) and increase the voltage enough to drive the speakers at the desired volume. A typical amplifier will have DC power supply rails at several 10s of Volts, plus and minus. The first amplifiers were based on triode valves, where a small voltage applied to one electrode allowed big currents to flow from the DC rails through the speakers. Later the bipolar junction transistor (BJT) and the metal–oxide–semiconductor field-effect transistor (MOSFET) were deployed.
Amplifiers just have to raise the output voltage to some multiple of the input voltage. Would be easy if those pesky speakers stopped allowing big currents to flow! Big currents cause a voltage drop according to Ohms’s Law, making it harder for the amplifier to get the output voltage where it should be.
Energy is what makes the light bulb light, not the current. Current is not consumed by the load. Proof, it returns to the source. Current measures the same on both sides of the load.
Energy is not consumed, it is transferred. It does not return to the source.
Where do I start? Overall, in our universe energy is conserved, so the light bulb converts some electrical energy into heat, some of which is converted into light. The energy comes from the power supply.
Power is usually measured in Watts and is calculated as the current times the voltage drop. Without current there is no electrical power. Electrical energy is power times time. It is usually measured in Watt-hours or kiloWatt-hours. In our light bulb circuit, current is conserved but the bulb consumes power as the voltage drops across its filament which has resistance. Ohm’s Law applies here as well as in speakers. Know any two of current, voltage drop and resistance and you can calculate the remaining quantity and the power.
Do things in the white paper sound familiar? Is Ian M. Sefton wrong too?
Yes they sound familiar but only because you keep repeating them ad nauseum! Yes, he is wrong. "The things the text books don’t tell you" contains things the text books don’t tell you because if they did, the text books would be wrong. I debunked his five major assertions in detail earlier. I marked each response QED, which coincidentally is the name of the maker of my main stranded, silver-plated copper speaker cables. They are spirally twisted around air-core tubes. Finally on-topic!
Ian M Sefton makes me ashamed to be an Australian,.really ...
I seem to recall that in another post you said you learnt your electricity from this forum?
No, I actually said:
I first learned how electricity works here on Agon in 2010. Oddly the thread was titled "directional cables?".
A member started posting about how an electrical signal actually travels down a wire. I thought what Planet is this guy from?...
Before 2010 I believed, like you, electrons traveled back an forth from the source to the load in a closed circuit. I believed , like you, AC current traveled back an forth from the source to the load in a closed circuit. I believed, like you, the AC signal traveled back an forth from the source to the load in the conductors.
I learned in 2010 what I was taught in K thru12 was wrong how electricity works.... Four years of electrical apprenticeship training I was taught the same wrong crap.
Basically Sefton and Morrison is saying the same thing.
Quote from Ralph Morrison.
If we accept the idea that fields carry energy in space, it must be true at all frequencies. That is the law. If it is true for light, it must also be true for 60Hz power and at DC. For utility power, the energy travels in the space between conductors, not in the conductors. This is not the picture presented by circuit diagrams, where energy seems to be carried by conductors. In digital circuits, the signals and energy travel in the spaces between traces or between traces and conducting surfaces.
Buildings have halls and walls. People move in the halls, not the walls. Circuits have traces and spaces. Signals and energy move in the spaces, not in the traces.
You don't believe any of that.
Your words:
AC or Alternating Current flows for a short period in one direction, then reverses direction repeatedly. Analog audio signals are AC,
I left you this Link below to read. If you would have taken the time to read over it you again would have found you are wrong. You would find the info is the same as Sefton and Morrison.
I think the answer is instantly. The switch is opened, Games over.
This was in response to what happens when a light is switched off, and of course the answer given is so wrong on so many levels!
When the light is on, it is because power is delivered in an electrical circuit featured by voltage and current - likely to be direct current in a car or alternating current in a home. When the current is suddenly interrupted because the switch is thrown, electrical pressure builds up at the switch. This pressure is known as voltage. If the current was big enough, the voltage becomes high enough to ionise the surrounding air and cause sparks at the switch contacts.
This is precisely the phenomenon used by older car ignition systems to generate very high voltages from 12-Volt DC electrical systems.
.
Context, of my quote, you used in your post above:
Okay, I got a simpler question, what if the load is disconnected before the energy gets there, what happens to that energy?
Can’t happen... The energy travels at near the speed of light. It’s at the light bulb the instant the contact closure completes the circuit... It’s that Fast!
Open the switch you break the voltage feeding the light bulb. Instantly, no light.
If you believe the electrons are moving back and forth in the wire and the electrons are what makes the light bulb light then you might have to wait quite while for the bulb to light up when you flip the switch on....
~ ~ ~
With that out of the way....
Source, 120Vac.
Load, 120V 100W incandescent light bulb.
Simple circuit,
120Vac source, SPST snap switch to disconnect source from load.
Close switch, a completed closed circuit is created.
Instantly EM wave energy flows in one direction >>>, at near the speed of light, from the source and is absorbed by the tungsten filament in the bulb. The energy is not consumed by the filament but rather is converted to to some other form of energy. Therein heat and light.
The event can’t happen unless there is a difference of potential, voltage, applied across both ends of tungsten filament in the bulb. Break the circuit, No longer a difference of potential, voltage, applied to the tungsten filament. Game over! No more light.
(I left out the part of the involvement of current, electric fields, and magnetic fields. All are needed to create the energy electromagnetic wave. Just trying to simplify the process.)
I don’t know what kind of lighting you have in, say, above a bathroom vanity in your home. If The light fixture uses incandescent light bulbs just go to the bathroom flip the wall switch on. Light instantly. Flip the switch off. Light’s gone instantly.
Electricity doesn’t work like water in in a garden hose. Water hose, turn off the faucet and water will continue running out of the hose. Electricity don’t work that way.
.
As for this:
This is precisely the phenomenon used by older car ignition systems to generate very high voltages from 12-Volt DC electrical systems.
Keeping it simple I’ll use a vehicles back when the electrical system, battery, was 6Vdc.
A high voltage coil is what stepped up 6Vdc to a high voltage for the spark plugs.I can’t remember how many thousands of volts it was back then.
The coil was, to me, a step up autotransformer. IF 6VDC was directly connected to the 6V pos and neg terminals on the coil it would work like an inductor. Not a transformer. A transformer only works when connected to an AC source. OR a pulsating DC voltage. So if you took the battery lead that feeds the neg terminal on the coil and momentarily touched it to the neg terminal on the coil, (completing the circuit), then remove the lead, (breaking the circuit) a high voltage would be induced on the high voltage winding. Electromagnet induction...
And that is the basics of how it works.
Of course for the ignition system of the vehicle there is a lot more to it. The thing that’s used to pulsate, make - and - break the 6Vdc to the coil primary winding is a spring loaded open and close set of "Points", contacts. A Condenser is wired across the set of contacts to extend the life of the contacts. There is a shaft on the distributor that is mechanically driven by the engine camshaft. It’s all about Timing! The distributor shaft has lobs on it that open and close the Points. There is a lot more to what goes on, but I’ll stop here...
@rodman99999What would the high voltage output of the coil look like on a engine diagnostic scope? Example... A choppy, say, the top half of an AC sine wave? Never really thought about it...
The voltage on those coils was in the 20-40K range, and everything was DC (6,12 or 24V).
DC voltage on an O-scope will just appear as a straight, horizontal line and read consistant with the scope’s voltage demarcations/setting.
On an engine analyzer: everythings zero, until the magnetic field in the coil collapses and the resultant high voltage is sent through the distributor, to a plug.
At that point: there’s a pronounced spike on the screen, repeated every time the points open and which appears very similar to an ECG trace, without the secondary pulse (lub sans dub).
But quantum entanglement has no practical applicability to music reproduction today.
Who said it did?
I pointed out: the phenomenon of information being instantaniously transmitted between entangled particles, has been accepted by Physicists, for decades.
ie: Even Einstein recognized the phenomenon, referrring to it as, "spooky action at a distance", 80 years ago.
I could have as easily used the phenomenon of a Bumblebee's ability to fly and that being accepted without explanation by the World's best Aeronautical and/or Aerospace Engineers, until Fluid Dynamics was developed. Only then could Dickinson use that science, to model how it could lift that fat butt into the air, with those tiny wings (circa 2005).
Another example might be why humans can smell/differentiate a vast multitude of odors*, with only something like 400 nasal receptors.
*some say 10K, some: a trillion.
21st Century experimentation in Quantum science says it's likely that our noses are actually listening to and recognizing the frequencies/sounds, generated by atoms and molecules, via quantum tunneling.
Okay, I was kinda done with this thread, but in response to this:
Can’t happen... The energy travels at near the speed of light. It’s at the light bulb the instant the contact closure completes the circuit... It’s that Fast!
Ponder this: You are watching a particular star on a clear night with your telescope, and suddenly you don’t see it anymore, you keep looking, perhaps it was blocked by a plane or some other object, or bent by some other huge object in a distant galaxy, but then after some length of time you are convinced that it must no longer be there, and how cool is that! You just witnessed a star burning out! You witnessed a star that had been burning for perhaps billions of years suddenly die! But in fact it "burned out" thousands of years before you were born- it just took that long for that last bit of light to reach your eyes.
Okay, I was kinda done with this thread, but in response to this:
Can’t happen... The energy travels at near the speed of light. It’s at the light bulb the instant the contact closure completes the circuit... It’s that Fast!
Ponder this: You are watching a particular star on a clear night with your telescope, and suddenly you don’t see it anymore, you keep looking, perhaps it was blocked by a plane or some other object, or bent by some other huge object in a distant galaxy, but then after some length of time you are convinced that it must no longer be there, and how cool is that! You just witnessed a star burning out! You witnessed a star that had been burning for perhaps billions of years suddenly die! But in fact it "burned out" thousands of years before you were born- it just took that long for that last bit of light to reach your eyes.
.
Distance from earth? Measured in light years. How many light years?
.
Quote:
Light is the fastest-moving stuff in our universe. It travels at 186,000 miles per second (300,000 km/sec). So, a light-year is 5.88 trillion miles (9.46 trillion km)."
.
Quote:
"The nearest stars to Earth are three stars that lie about 4.37 light-years away in the Alpha Centauri triple-star system. The closest of these stars, Proxima Centauri, is just about 4.24 light-years away."
.
Average distance in your home for a light switch to a light fixture.
For those who find it hard or impossible to visualise how a signal can travel faster than the stuff it travels through, consider how sound reaches your ears from a loud speaker.
Air comprises molecules randomly whizzing about in all directions, and sometimes colliding with each other and the surroundings. When the speaker cone moves forward, some of the nearby molecules get a slight extra shove in the forward direction. They pass this extra shove to the molecules near them, and so on.. The extra shove reaches your ears at the speed of sound, but no molecule has to directly travel from the loudspeaker to your ear, let alone at the speed of sound There is no need for a sonic jetstream,
This is similar to the behaviour of the cloud of free electrons whizzing about in a metal, responding to a voltage signal.
Or think of a long train (our record in Australia is 4.5 miles long with 682 cars and 8 locomotives), The couplers between the cars are designed to have a small amount of slack so overall the train stretches when pulled and compresses when braked. Imagine the train is stopped. Apply power to the lead locomotive, and the coupling to the next car will stretch a bit before that car starts to move. The process ripples down the length of the train. After a short while, the signal that the train is moving arrives at the last car (a mile or more from the loco) though overall not one of the cars has moved more than a few yardsl.
I learned in 2010 what I was taught in K thru12 was wrong how electricity works.... Four years of electrical apprenticeship training I was taught the same wrong crap
Nevertheless, it would be helpful if you could remember how to apply Ohm's Law, and how power is calculated in electrical circuits! Fortunately, when wiring houses, you don't need to work things out from first principles, because engineers have done this for you and experts have written building codes to follow.
My partner's son leads a crew working on high voltage transmission lines running hundreds of thousands of Volts, but in Australia he is not officially qualified to install a 240-Volt outlet in his own home! That would be against government regulations.
Talking of government, a while ago I sold an upgrade to The Canberra Hospital's digital imaging system, which was the source of all patient records. I included a big uninterruptible power supply (UPS) with rectifiers, batteries and inverters. The hospital insisted that their own electricians do the installation. When I inspected the finished system, there was a computer room with hospital grade power outlets, red for the high-availability outlets, beautifully run back through a distribution system to the UPS. But the UPS only had one cable connected - the output. The electricians (we call them sparkies in Australia) had "forgotten" to run mains power to the UPS.
"If we accept the idea that fields carry energy in space, it must be true at all frequencies. That is the law. If it is true for light, it must also be true for 60Hz power and at DC. For utility power, the energy travels in the space between conductors, not in the conductors. This is not the picture presented by circuit diagrams, where energy seems to be carried by conductors. In digital circuits, the signals and energy travel in the spaces between traces or between traces and conducting surfaces.
Buildings have halls and walls. People move in the halls, not the walls. Circuits have traces and spaces. Signals and energy move in the spaces, not in the traces."
No, I could not be bothered but I will have a little crack at him now!
If it is true for light, it must also be true for 60Hz power and at DC.
Light is an example of electromagnetic radiation which can be visualised in classical physics as synchronised oscillations of electric and perpendicular magnetic fields. In a vacuum, they travel at the speed of light.
They are reinterpreted in quantum physics as streams of photons, which are uncharged particles with zero mass when they are at rest. Photons do not obey the Pauli exclusion principle.
In this context, 60-Hz power and DC surely refer to electricity? 60-Hz electromagnetic waves are very low frequency radio waves! DC is not any sort of wave.
Electricity is the result of charge, and charges are carried by electrons and other particles which do obey the Pauli exclusion principle. Similar charges strongly repel, and opposite charges strongly attract. Richard Feynman has stated that every electron affects every other electron in our universe.
Electric currents are not a form of Electromagnetic radiation - Wikipedia. Mr Morrison is confusing photonics and electronics (electricity in particular). Having got that fundamentally wrong, his assertion that electrical energy is carried in the spaces between conductors is equally wrong.
His speciality seems to be circuit board layout for digital circuits. His message is to beware of interference between adjacent traces, especially in multi-layered applications. This is good advice, not because of electromagnetic radiation, but because every electron interacts with every other electron. (Photons are much better behaved!).
In digital circuits, the signals and energy travel in the spaces between traces or between traces and conducting surfaces
Surely traces are conducting surfaces?
The circuit board traces are the conductive halls filled with crowds of free electrons.
Finally, digital circuits typically operate at or near Gigahertz switching rates. The skin effect is very important at these rates. Almost always the switching is done in integrated circuits based on doped semi-conductors, not conducting metals. The quantum properties of the electron turn this subject from electrics into electronics, often at the nano-scale.
If Mr Morrison believes in his "law" he should change his title to "What is photonics"
Or think of a long train (our record in Australia is 4.5 miles long with 682 cars and 8 locomotives), The couplers between the cars are designed to have a small amount of slack so overall the train stretches when pulled and compresses when braked. Imagine the train is stopped. Apply power to the lead locomotive, and the coupling to the next car will stretch a bit before that car starts to move. The process ripples down the length of the train. After a short while, the signal that the train is moving arrives at the last car (a mile or more from the loco) though overall not one of the cars has moved more than a few yards.
and:
Richard Feynman has stated that every electron affects every other electron in our universe.
How many times the Dunning-Kruger exemplar above has mentioned Richard Feynman and/or QED, without the first clue as to the workings of his/its basic theory, would be hilarious, were it no so pathetic.
I was in charge of wiring the power to feed MRI Rooms, Cat Scan rooms, Countless numbers of X-Ray Rooms.
I believe that is more in lines with roughing in the electrical to the rooms, but more in line with this thread, I am curious if were able to see the power cords connecting those machines; any directionality on them?
I don't know if you are aware, but Shunyata claims to have some of its power cables in some hospitals as the filters and shielding reduce noise on the heart monitors and enable the doctors to better read the data from them. Not sure if any have made their way to MRI's etc.
I believe that is more in lines with roughing in the electrical to the rooms, but more in line with this thread, I am curious if were able to see the power cords connecting those machines; any directionality on them?
Nope...
I wouldn’t even bring up wire directionality to a fellow electrician. Or how electrical energy, power, actually travels from an AC source to a connected load. They would look at me like I was nuts... To the average electrician AC current flows back and forth in a closed electrical circuit. E = I x R... P = E x I. They measure current with a Clamp Amp meter. Current does the work... Current makes the filament in the light bulb light.
I am not saying all Journey wireman electricians today are of the same mind set.
Especially Master Electricians.
I don’t know if you are aware, but Shunyata claims to have some of its power cables in some hospitals as the filters and shielding reduce noise on the heart monitors and enable the doctors to better read the data from them. Not sure if any have made their way to MRI’s etc.
I remember reading that too. To be honest with you I never looked at any of the power cords used in a hospital.
(FWIW, I never considered the wire in a 120Vac power cord was directional. You can’t really check for yourself. It comes with a male and female connector. Now an interconnect, what signal voltage are we dealing with? Maybe around 2V, usually less sometimes?)
I can tell you any power cord used in a patient care area are UL Listed hospital grade and have Hospital Grade connectors. Who was in charge to made sure they were? It was either Bio Med or Bio Tech. Every receptacle outlet in patient care rooms, ER, OR, ICU CCU, Cath Labs, others I can’t think of, were inspected by either Bio med or Bio Tech, (can’t remember which one), for any exterior damage and checked the equipment ground contact of the outlet for a minimum of 4 ounces of contact pull out holding contact pressure. They had a device they plugged into the outlet that had a mechanical pointer that indicated the pulling out resistance in ounces. I can’t remember how often they tested the outlets. But I bet they checked power cords as well when checking the wall outlets, to make sure they were UL Listed Hospital Grade, and checked for any signs of damage.
.
One thing I do remember. The shop, the electrical Contractor I worked for, shop Branch Manager, without consulting me first, gave the hospital a price to change out all the 20A duplex wall outlets in patient rooms on two floors of a wing in the hospital. It was a competitive bid job, Therein bidding against another Electrical Contractor. Well he was the low bidder. He got the job. Problem? For the hospital grade duplex wall outlets, an electrical wholesale house salesman gave him great price on a bulk order of Pass & Seymour 20A 8300 hospital grade duplex receptacle outlets. At the time I was ordering, using, a good quality Leviton 8300 hospitable grade duplex receptacle outlets. They held up good compared, against, the high dollar 20A Hubbell 8300 outlets.
You just just don’t change the manufacturer of a hospital grade electrical outlet used in a hospital. Not that hospital anyway. I got the in house electrical department shop foreman to consider the Leviton 8300 outlet. I gave him a couple and told him to physically abuse the hell out of them. Let me know what he thought of them. He got back with me and gave me approval to use them instead of the high dollar Hubbell 8300 outlets.
.
Cut to the case, my boss said that’s what he bid that’s what will be installed. Fine!
So I had my electricians install the P&S outlets. LOL, you just don’t walk into a patient room, that has a patient in it, and change out wall outlets. You talk to the floor nurse manager, Very nicely, and say "I have been hired to change out all the wall outlets in patient rooms on the floor." "Would you please call me on my cell phone and let me know when a room, or maybe rooms, are empty and available."
She might say something like, "Yeah, I heard they had to be replaced."
Next thing out her mouth, "How long will you tie up my patient bed,.. the room?" Get an idea what you are dealing with? A lot of wasted non productive time. Time Is Money!
About a year later I got a call from Bio-med or Bio tech asking me if I installed new outlets on two floors in the so, so, wing. LOL, they knew I did... Next words out of the guys mouth we started testing the outlets on one of the floors and outlets are failing the test.
Not B.S. They explain it if you’d just read the instructions. Worlds Best Cables simply say this: These Quad RCA cables are configured as directional cables, we strongly believe that this is the most appropriate topology for best performance and superior noise rejection characteristics. Most cable assemblers will either leave the shield floating at both ends or grounded at both ends which makes it easier to assemble but inferior in performance. We do not take such shortcuts.
What does "Directional" mean: This simply refers to the construction, which is depicted in their included diagram, which shows the shield, which is connected to the ground at the signal emitting end acts as a Faraday cage which rejects external noise that could degrade the signal. The cable will work even if you connect it the wrong way, but this will diminish the noise rejection capabilities of the cable.
---|
I work with several electrical engineers and they concur with the above. Does it make any "real world" difference? That will depend on the electrical environment of your equipment and how "noisy" it is. But it doesn’t hurt to be erring on the side of reducing possible interference. I mean, short of using balanced cables for every single interconnect (something not possible on most devices), using cables that are "directional" seems to be the next best thing.
Did you do your practical hospital wiring based on the "false" teachings from your apprenticeship, or based on what you learned here? Be honest.
Maybe you were the sparkie that "forgot" to connect The Canberra Hospital's UPS to the mains supply?
Perhaps you could restate your understanding of electrical energy, as set out below, so it makes sense? You might care to include the effects of resistance and voltage ... and the relationship between power and energy:
Energy is what makes the light bulb light, not the current. Current is not consumed by the load. Proof, it returns to the source. Current measures the same on both sides of the load.
Light is the fastest-moving stuff in our universe. It travels at 186,000 miles per second (300,000 km/sec)
I'd add "in a vacuum" just for completeness.
You would, I hope, agree that low frequency electromagnetic waves are radio waves and travel at the speed of light.
So would you dispute that the wavelength of 60-Hz radio waves in a vacuum is 186,000 / 60 or about 3,100 miles? That's about the radius of our planet.
Do you really think the conductors in a circuit board radiate any detectable amount of 60-Hz radio waves?
You might care to read up on the difficulty of communicating with submerged submarines using extremely low frequency radio - see Communication with submarines - Wikipedia
Did you do your practical hospital wiring based on the "false" teachings from your apprenticeship, or based on what you learned here? Be honest.
I did electrical wiring after 2010 the same way as I did before 2010. Why would you think I would do it any different?
Knowing how energy actually flows from the source >>> to the Load doesn’t change anything as for installing electrical wiring.
To keep it as simple as I can for you... Example: A customer has a new piece of equipment he wants connected to electrical power. He may have a spec sheet that specifies what the manufacturer requires for the minimum electrical wiring requirements. Usually it just says it must be wired to meet NEC code. (Not Always)
If nothing is given the name/data plate on the equipment is used. The data plate will show the Phase, voltage, and the FLA (Full Load Amps).
Per NEC, (National Electrical Code), the branch circuit wiring is sized using the FLA times 125%. If the FLA is 27A, 1.25 X 27A = 33.75A. Table 310-16, (and notes), wire size? #8awg copper. That’s It.... Phase, Voltage, and Full load current. (Note: Motor loads use different wire sizing calculations)
Nothing said about current "flowing" back an forth in a circuit. Nothing said about energy flowing in one direction either... Phase, Voltage, and Full load current... (Note, there are, will be, maybe, other things the electrician must take into account, for the wiring method he uses. I kept it simple, for you.
Thank you for your honesty, You do your wiring the same before and after you ’learnt’ how electricity really works on this forum.
I really don’t think the author needed to say, in a vacuum...
No, but as a physicist I just had to add that nuance before I got accused of getting it wrong! Light slows down in water, glass or plastic by a ratio corresponding to the refractive index of the medium.
In fibre-optic cables, light normally arrives faster if it travels straight down the middle, than it does when bouncing at an angle off the inner surface. This is simply because it has further to travel. So at the end of the transmission, the light is smeared out in time depending on the path it took, which is not good for digital signals
Clever manufacturers use glass with a higher refractive index at the centre, getting lower towards the edges. This is done by changing the composition of glass vapour during vacuum deposition when building up a glass slug. The slug is subsequently drawn into a very fine fibre. The higher refractive index at the centre is designed to slow straight-through photons so the signal arrives all at once, more or less. Obviously this is more important for undersea cables than for component connections, but hey .... if marketed properly some will buy in.
Did you know that space has negative energy? Create more space, and you create more vacuum into which things can "fall". Or that quantum space is not really empty - particles and anti-particles appear and annihilate randomly. That is a credible way to create a universe from almost nothing
....and checked the equipment ground contact of the outlet for a minimum of 4 ounces of contact pull out holding contact pressure. They had a device they plugged into the outlet that had a mechanical pointer that indicated the pulling out resistance in ounces. I can’t remember how often they tested the outlets. ... Next words out of the guys mouth we started testing the outlets on one of the floors and outlets are failing the test.
@jea48It seems really odd to me that nobody has invented a simple locking mechanism for hospital outlets, or simply use some sort of L14 30R plug like they have on generators to ensure it remains where it should. It is not about contact pressure for "better signal", it is about the likelihood of a plug to become dislodged. How much money would hospitals save by doing this, instead of the frequent inspections which must add up to some serious coin.
....and checked the equipment ground contact of the outlet for a minimum of 4 ounces of contact pull out holding contact pressure. They had a device they plugged into the outlet that had a mechanical pointer that indicated the pulling out resistance in ounces. I can’t remember how often they tested the outlets. ... Next words out of the guys mouth we started testing the outlets on one of the floors and outlets are failing the test.
@jea48It seems really odd to me that nobody has invented a simple locking mechanism for hospital outlets, or simply use some sort of L14 30R plug like they have on generators to ensure it remains where it should. It is not about contact pressure for "better signal", it is about the likelihood of a plug to become dislodged. How much money would hospitals save by doing this, instead of the frequent inspections which must add up to some serious coin.
.
It is not about contact pressure for "better signal", it is about the likelihood of a plug to become dislodged.
IT is absolutely about contact pressure. Especially the contact pressure of the female safety equipment ground contact to the plug equipment ground pin. A good low impedance connection is a must...
The worst physical abuser of a hospital grade receptacle, that a patient’s bed is plugged into, is the house keeper that scrubs the floor in the room. ??? I actually seen it first hand. The house keeper unlocks the brakes on the bed and gives it hard shove to one side so the floor under the bed can be cleaned. The cord on the bed is only so long. The extreme side pressure on the plug rips it right out of the receptacle. That abuse of the receptacle contacts, especially the equipment ground contact can go well beyond the designed contact holding memory retention.
Hubbell and Leviton hospital grade receptacles can take repeated physical abuse for years. The Pass & Seymour 20A, 8300 hospital grade duplex receptacle outlets made it about one year. There is a very chance they didn’t last that long...
You must have a verified phone number and physical address in order to post in the Audiogon Forums. Please return to Audiogon.com and complete this step. If you have any questions please contact Support.
