Power distribution, was: 2-wire, unpolarized outlet ?
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No, I read it correctly.? You are proposing a distinction without a difference.? The Edison system was developed to reduce the number of conductors and the cost in a power distribution system, a benefit applied equally well to both DC and AC systems. Might as well debunk another myth that AC is more efficient then DC in power distribution.? The main losses in both systems is due to wire resistance but AC distribution also has reactive and skin effect losses that DC distribution does not have.? AC power distribution is perhaps more convenient but?it is less efficient.?? See:?? Regards from a snowy Arkansas, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Friday, January 10, 2025 at 11:53:47 AM CST, Donald J via groups.io <djeffarndt@...> wrote:
You did not read that right It is similar but not the Edison system - the one we use is SIMILAR to the Edison split DC system! A?split-phase?or?single-phase three-wire?system is a type of??distribution. It is the??(AC) equivalent of the original??three-wire??system. Its primary advantage is that, for a given capacity of a distribution system, it saves conductor material over a single-ended single-phase system. On Fri, Jan 10, 2025 at 10:25?AM Jim Whartenby via <old_radio=[email protected]> wrote:
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Just pointing out that is it no longer called the Edison system Any relation to Edison is now gone so stop calling it that The only Edison we have kept is his light bulb screw and it socket On Fri, Jan 10, 2025 at 2:30?PM Jim Whartenby via <old_radio=[email protected]> wrote:
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Long range DC distribution is not practical as we have proven many times over Under the Edison system EVERY block in New York had to have its own generator as running the DC more than a block was to cost prohibitive as the wire became so thick On Fri, Jan 10, 2025 at 2:30?PM Jim Whartenby via <old_radio=[email protected]> wrote:
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Donald You are mistaken.? See:?? for a very long list of existing HVDC transmission projects. Regards, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Friday, January 10, 2025 at 01:44:27 PM CST, Donald J via groups.io <djeffarndt@...> wrote:
Long range DC distribution is not practical as we have proven many times over Under the Edison system EVERY block in New York had to have its own generator as running the DC more than a block was to cost prohibitive as the wire became so thick On Fri, Jan 10, 2025 at 2:30?PM Jim Whartenby via <old_radio=[email protected]> wrote:
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开云体育Let’s try to make peace with AC and DC power this way -- ? From: [email protected] <[email protected]> On Behalf Of Jim Whartenby via groups.io
Sent: Friday, January 10, 2025 1:34 PM To: [email protected] Subject: Re: [HallicraftersRadios] Power distribution, was: 2-wire, unpolarized outlet ? ? Donald You are mistaken.? See:?? for a very long list of existing HVDC transmission projects. Regards, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy ? ? On Friday, January 10, 2025 at 01:44:27 PM CST, Donald J via groups.io <djeffarndt@...> wrote: ? ? Long range DC distribution is not practical as we have proven many times over ? Under the Edison system EVERY block in New York had to have its own generator as running the DC more than a block was to cost prohibitive as the wire became so thick ? ? ? On Fri, Jan 10, 2025 at 2:30?PM Jim Whartenby via <old_radio=[email protected]> wrote:
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Donald "Now gone?" that's really funny!? Even professional electricians still call it the "Edison three wire system."? See:? Might as well to try to discourage the old terms: 110 volts, 115 volts, 117 volts conventions, cps versus Hertz and the use of Ohm's Law to describe power.? This is properly know as Joule's Law but good luck with that.? Regards, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Friday, January 10, 2025 at 01:41:41 PM CST, Donald J via groups.io <djeffarndt@...> wrote:
Just pointing out that is it no longer called the Edison system Any relation to Edison is now gone so stop calling it that The only Edison we have kept is his light bulb screw and it socket On Fri, Jan 10, 2025 at 2:30?PM Jim Whartenby via <old_radio=[email protected]> wrote:
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开云体育Another reason (other than the transmission losses) to use HVDC transmission lines is to be able to sync together (at 50 or 60 Hz) various parts of the power grids. The power provided by Hydro Quebec, for example, to New York City, will have required to sync the whole Hydro-Quebec grid to the one of the New York state (the reverse was less likely). I believe I already posted about the line from James Bay to Montreal which runs at 735kV AC. It was long debated in the Hydro-Quebec Engineering Dept. that this line should have used HVDC, but because it have only one destination (Montreal area) it has been feasible to design a proper phase compensation system that take care of the varying loads at the end of the line. Remark here that this power line is near to a quarter wave long at 60 Hz ! It also means that all the generators in James Bay central have to turn almost a quarter of a cycle IN ADVANCE to the ones that are used at Beauharnois (near Montreal). 贵补蝉肠颈苍补迟颈苍驳… ? 73, Jacques, VE2JFE in Montreal ? A fascinating list, I didn't realize there were so many. Many years |
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Depends on the year!? Sometime in the 1950's, the line voltage convention was changed from 117 to 120 so the choices were 117 / 234 then and 120 / 240 now.? 115 volts was proposed in 1927 in the NEMA Radio Standards when AC power was first used to power commercial radio receivers. See enclosure, second column, "Ratings."? 110 / 220 was Edison's DC voltage convention which seems to have continued on in appliance specifications when AC became the norm.? ? Times change, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Friday, January 10, 2025 at 03:26:10 PM CST, Nick, W1NJC via groups.io <njc@...> wrote:
Is it "220" or "240"??
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Nick There are many who feel as you do.?? I would check the tube heater voltage at the tube socket.? If it is within 10% of 6.3 volts then all is OK according to the vacuum tube manuals.? I am of the opinion that heat is the real enemy of reliability, not line voltage.? The cooler the chassis is, the longer the tubes (and everything else) will last.? For this reason, I advocate replacing tube rectifiers with silicon.? Less heat is good, a bit higher B+ doesn't mean a thing but a cooler running power transformer does. Just like with lightbulbs, it is the ON/OFF cycling that is the vacuum tube killer. Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Friday, January 10, 2025 at 04:14:22 PM CST, Nick, W1NJC via groups.io <njc@...> wrote:
I always use a variac on my vintage gear set to about 115V to keep the filaments safe.? My line V is about 121/242 but at a previous residence it was sitting around 108V!
I still hear people say "220" when they mean 240V.? I've also heard "house current" and "mains power".
Go to the EU and you'll find 230V, 50Hz (UK is/was 240V), and of course those funky outlets.
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开云体育Nick, Re I still hear people say "220" when they mean 240V.? How do you know which they mean? Right here the laws for 240 Vs 220 ??are simple, but complicated. ?You put 240V 0r 120 into your long extension and get 220 or 110 out at ?your compressor operating next to your vehicle, even though you have a #12 cord. Blame mr Ohm and others from back then ?in early 1800’s who made our laws!!! ? From: [email protected] [mailto:[email protected]] On Behalf Of Nick, W1NJC via groups.io
Sent: Friday, January 10, 2025 5:14 PM To: [email protected] Subject: Re: [HallicraftersRadios] Power distribution, was: 2-wire, unpolarized outlet ? ? I always use a variac on my vintage gear set to about 115V to keep the filaments safe.? My line V is about 121/242 but at a previous residence it was sitting around 108V! I still hear people say "220" when they mean 240V.? I've also heard "house current" and "mains power". Go to the EU and you'll find 230V, 50Hz (UK is/was 240V), and of course those funky outlets.
-- don??? va3drl |
开云体育This is unfortunately a continuation of a part of the off-topic stuff that brings down the respect of our forum, but must be done. Re ??the wording that began in a different topic /g/HallicraftersRadios/message/31466 ?and somehow has been continued in this topic and that continues a dispute is:? ?? “Yes, it is known as the Edison split phase system, see: ” I previously glossed over the above wording believing that a comma was just accidentally missing, and knowing people often use loose wording to express difficult stuff, however when looking at the quoted link, I see the following: ? quote ????? “A split-phase or single-phase three-wire system is a type of distribution. ??It is the (AC) equivalent of the original three-wire ” ? End quote ???and not “Edison split phase system” The term “split-phase” is used frequently in the above link , and ?“Edison” is used twice, but not beside “split-phase” or “split phase”. ? Now, Re?? the previously quoted ? Here is what I see in that quoted text at the top on my bit-machine and screen with my old eyes: Ask An Electrician - How Does Edison 3 Wire (Split Phase) System Work? As I see it , [with? added spaces,color, etc ?for clarity ] the area in dispute says : Edison 3 Wire ???( Split Phase ) ???System. ? I read that in my grammar as: ? Edison 3 Wire ???or ???Split Phase ???System … Which ?means to me that the system can be identified by either ? 1-? ?the term ?“Edison 3 Wire” ??????? ????????or 2-? the term ?“Split Phase” ?? ?????the term ?“single-phase three-wire” is perhaps more clear ?in a multi-phase environment And intentionally misquoting it as ?“Edison split phase system” and then reinforcing it seems to me to be intentionally part of the “misinformation” society that is plaguing this side of the world. ? see
?quote Misinformation is false or inaccurate information—getting the facts wrong. Disinformation is false information which is deliberately intended to mislead—intentionally misstating the facts. The has affected our ability to improve public health, address climate change, maintain a stable democracy, and more. By providing valuable insight into how and why we are likely to believe misinformation and disinformation, psychological science can inform how we protect ourselves against its ill effects. End quote ??? -- don??? va3drl |
开云体育Tumbs up, Don. ? 73, Jacques, VE2JFE in Montreal ? De?: [email protected] <[email protected]> De la part de don Root ? This is unfortunately a continuation of a part of the off-topic stuff that brings down the respect of our forum, but must be done. Re ??the wording that began in a different topic /g/HallicraftersRadios/message/31466 ?and somehow has been continued in this topic and that continues a dispute is:? ?? “Yes, it is known as the Edison split phase system, see: ” I previously glossed over the above wording believing that a comma was just accidentally missing, and knowing people often use loose wording to express difficult stuff, however when looking at the quoted link, I see the following: ? quote ????? “A split-phase or single-phase three-wire system is a type of distribution. ??It is the (AC) equivalent of the original three-wire ” ? End quote ???and not “Edison split phase system” The term “split-phase” is used frequently in the above link , and ?“Edison” is used twice, but not beside “split-phase” or “split phase”. ? Now, Re?? the previously quoted ? Here is what I see in that quoted text at the top on my bit-machine and screen with my old eyes: Ask An Electrician - How Does Edison 3 Wire (Split Phase) System Work? As I see it , [with? added spaces,color, etc ?for clarity ] the area in dispute says : Edison 3 Wire ???( Split Phase ) ???System. ? I read that in my grammar as: ? Edison 3 Wire ???or ???Split Phase ???System … Which ?means to me that the system can be identified by either ?
????????or
?????the term ?“single-phase three-wire” is perhaps more clear ?in a multi-phase environment And intentionally misquoting it as ?“Edison split phase system” and then reinforcing it seems to me to be intentionally part of the “misinformation” society that is plaguing this side of the world. ? see
?quote Misinformation is false or inaccurate information—getting the facts wrong. Disinformation is false information which is deliberately intended to mislead—intentionally misstating the facts. The has affected our ability to improve public health, address climate change, maintain a stable democracy, and more. By providing valuable insight into how and why we are likely to believe misinformation and disinformation, psychological science can inform how we protect ourselves against its ill effects. End quote ???
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Don I'm really confused by your post and the casual use of terms.? I assume that you are still annoyed by the use of "Edison" to describe the center tapped transformer distribution system currently in use? There were three systems proposed to transmit power early on (1883-1896, see:? ) in the US and perhaps Canada too.? They are single phase (Westinghouse), two phase aka polyphase (Tesla)?and three phase (Dolivo-Dobrovolsky).? Tesla was the champion of the two phase system where the two phases are separated by 90 degrees, in the 3 phase system, 120 degrees separates each phase.? The three phase system eventually won the day. Some sources credit Tesla with the three phase motor (patent filed in 1897) but his patent specified six wires connecting the motor to the generator.? This is not what is used today.? Dolivo-Dobrovolsky a Russian born German working for AEG developed the three phase system now in use along with the delta-wye configuration, the three phase motor (1888), three phase transformer and he designed the first three phase hydroelectric power plant (1891) using all of his developments. The split phase or Edison distribution system is part of the single phase system.? The use of the term "multi-phase" is a distortion of facts and implies a three phase system which it is clearly not.? Yes, Edison developed his system for the lights powered by the Pearl Street Station which used a "neutral" and two "hot" conductors.? From one hot conductor to neutral was 110 VDC and across both hot conductors was 220 VDC.? This configuration is still used today but at a slightly higher voltage using AC power but the principle is still valid and Edison still deserves the credit.?? Regards, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Sunday, January 12, 2025 at 08:25:11 PM CST, don Root <drootofallevil@...> wrote:
This is unfortunately a continuation of a part of the off-topic stuff that brings down the respect of our forum, but must be done. Re ??the wording that began in a different topic /g/HallicraftersRadios/message/31466 ?and somehow has been continued in this topic and that continues a dispute is:? ?? “Yes, it is known as the Edison split phase system, see: ” I previously glossed over the above wording believing that a comma was just accidentally missing, and knowing people often use loose wording to express difficult stuff, however when looking at the quoted link, I see the following: ? quote ????? “A split-phase or single-phase three-wire system is a type of distribution. ??It is the (AC) equivalent of the original three-wire ” ? End quote ???and not “Edison split phase system” The term “split-phase” is used frequently in the above link , and ?“Edison” is used twice, but not beside “split-phase” or “split phase”. ? Now, Re?? the previously quoted ? Here is what I see in that quoted text at the top on my bit-machine and screen with my old eyes: Ask An Electrician - How Does Edison 3 Wire (Split Phase) System Work? As I see it , [with? added spaces,color, etc ?for clarity ] the area in dispute says : Edison 3 Wire ???( Split Phase ) ???System. ? I read that in my grammar as: ? Edison 3 Wire ???or ???Split Phase ???System … Which ?means to me that the system can be identified by either ? 1-? ?the term ?“Edison 3 Wire” ??????? ????????or 2-? the term ?“Split Phase” ?? ?????the term ?“single-phase three-wire” is perhaps more clear ?in a multi-phase environment And intentionally misquoting it as ?“Edison split phase system” and then reinforcing it seems to me to be intentionally part of the “misinformation” society that is plaguing this side of the world. ? see
?quote Misinformation is false or inaccurate information—getting the facts wrong. Disinformation is false information which is deliberately intended to mislead—intentionally misstating the facts. The has affected our ability to improve public health, address climate change, maintain a stable democracy, and more. By providing valuable insight into how and why we are likely to believe misinformation and disinformation, psychological science can inform how we protect ourselves against its ill effects. End quote ??? -- don??? va3drl |
开云体育Jim, ??from ?your 3rd paragraph and the references I agree with the phrase? “split phase or Edison” ?for AC? systems with the OR included. I agree Edison was the big man for DC, and he should not be forgotten. And that 3-Wire DC system was copied for AC. ? ? Thanks for that interesting link to way back. You no doubt notice that the letters ”ground” do ?not appear. ? I am quite aware of the development of AC, but my past “research” leaves exactly who did what first as an ongoing debate. I have a few Tesla books that I got at the AWA Rochester 30 years ago. ? The use of the term "multi-phase": ?
???“Multi-phase power generation designs with 5, 7, 9, 12, and 15 phases in conjunction with “ ? ? From: [email protected] [mailto:[email protected]] On Behalf Of Jim Whartenby via groups.io
Sent: Monday, January 13, 2025 4:15 AM To: [email protected] Subject: Re: [HallicraftersRadios] Power distribution, was: 2-wire, unpolarized outlet ? ? Don I'm really confused by your post and the casual use of terms.? I assume that you are still annoyed by the use of "Edison" to describe the center tapped transformer distribution system currently in use? ? There were three systems proposed to transmit power early on (1883-1896, see:? ) in the US and perhaps Canada too.? They are single phase (Westinghouse), two phase aka polyphase (Tesla)?and three phase (Dolivo-Dobrovolsky).? Tesla was the champion of the two phase system where the two phases are separated by 90 degrees, in the 3 phase system, 120 degrees separates each phase.? The three phase system eventually won the day. ? Some sources credit Tesla with the three phase motor (patent filed in 1897) but his patent specified six wires connecting the motor to the generator.? This is not what is used today.? Dolivo-Dobrovolsky a Russian born German working for AEG developed the three phase system now in use along with the delta-wye configuration, the three phase motor (1888), three phase transformer and he designed the first three phase hydroelectric power plant (1891) using all of his developments. ? The split phase or Edison distribution system is part of the single phase system.? The use of the term "multi-phase" is a distortion of facts and implies a three phase system which it is clearly not.? Yes, Edison developed his system for the lights powered by the Pearl Street Station which used a "neutral" and two "hot" conductors.? From one hot conductor to neutral was 110 VDC and across both hot conductors was 220 VDC.? This configuration is still used today but at a slightly higher voltage using AC power but the principle is still valid and Edison still deserves the credit.?? Regards, Jim ? Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy ? ? On Sunday, January 12, 2025 at 08:25:11 PM CST, don Root <drootofallevil@...> wrote: ? ? This is unfortunately a continuation of a part of the off-topic stuff that brings down the respect of our forum, but must be done. Re ??the wording that began in a different topic /g/HallicraftersRadios/message/31466 ?and somehow has been continued in this topic and that continues a dispute is:? ?? “Yes, it is known as the Edison split phase system, see: ” I previously glossed over the above wording believing that a comma was just accidentally missing, and knowing people often use loose wording to express difficult stuff, however when looking at the quoted link, I see the following: ? quote ????? “A split-phase or single-phase three-wire system is a type of distribution. ??It is the (AC) equivalent of the original three-wire ” ? End quote ???and not “Edison split phase system” The term “split-phase” is used frequently in the above link , and ?“Edison” is used twice, but not beside “split-phase” or “split phase”. ? Now, Re?? the previously quoted ? Here is what I see in that quoted text at the top on my bit-machine and screen with my old eyes: Ask An Electrician - How Does Edison 3 Wire (Split Phase) System Work? As I see it , [with? added spaces,color, etc ?for clarity ] the area in dispute says : Edison 3 Wire ???( Split Phase ) ???System. ? I read that in my grammar as: ? Edison 3 Wire ???or ???Split Phase ???System … Which ?means to me that the system can be identified by either ? 1-? ?the term ?“Edison 3 Wire” ??????? ????????or 2-? the term ?“Split Phase” ?? ?????the term ?“single-phase three-wire” is perhaps more clear ?in a multi-phase environment And intentionally misquoting it as ?“Edison split phase system” and then reinforcing it seems to me to be intentionally part of the “misinformation” society that is plaguing this side of the world. ? see
?quote Misinformation is false or inaccurate information—getting the facts wrong. Disinformation is false information which is deliberately intended to mislead—intentionally misstating the facts. The has affected our ability to improve public health, address climate change, maintain a stable democracy, and more. By providing valuable insight into how and why we are likely to believe misinformation and disinformation, psychological science can inform how we protect ourselves against its ill effects. End quote ???
_._,_._,_ -- don??? va3drl |
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Don According to Mr. A.I. Google, the grounding of the neutral line became mandatory with the 1913 update to the NEC.? Grounding of the building service was not explicitly required until 1918.? It seems that the NEC has always been a work in progress.??My search terms were: "when did the NEC require that the neutral line be grounded" and "when did NEC require grounded outlets". Tesla, Sarnoff, Armstrong, de Forest, Shockley, Collins, among many others, are all demigods, some with a vocal cult following, others with vocal detractors.? For me it would be Oliver Heaviside and John Costas to name two relatively unknows but both have made great contributions in the field of electrical engineering. Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Monday, January 13, 2025 at 05:25:14 AM CST, don Root <drootofallevil@...> wrote:
Jim, ??from ?your 3rd paragraph and the references I agree with the phrase? “split phase or Edison” ?for AC? systems with the OR included. I agree Edison was the big man for DC, and he should not be forgotten. And that 3-Wire DC system was copied for AC. ? ? Thanks for that interesting link to way back. You no doubt notice that the letters ”ground” do ?not appear. ? I am quite aware of the development of AC, but my past “research” leaves exactly who did what first as an ongoing debate. I have a few Tesla books that I got at the AWA Rochester 30 years ago. ? The use of the term "multi-phase": ?
???“Multi-phase power generation designs with 5, 7, 9, 12, and 15 phases in conjunction with “ ? ? From: [email protected] [mailto:[email protected]] On Behalf Of Jim Whartenby via groups.io
Sent: Monday, January 13, 2025 4:15 AM To: [email protected] Subject: Re: [HallicraftersRadios] Power distribution, was: 2-wire, unpolarized outlet ? ? Don I'm really confused by your post and the casual use of terms.? I assume that you are still annoyed by the use of "Edison" to describe the center tapped transformer distribution system currently in use? ? There were three systems proposed to transmit power early on (1883-1896, see:? ) in the US and perhaps Canada too.? They are single phase (Westinghouse), two phase aka polyphase (Tesla)?and three phase (Dolivo-Dobrovolsky).? Tesla was the champion of the two phase system where the two phases are separated by 90 degrees, in the 3 phase system, 120 degrees separates each phase.? The three phase system eventually won the day. ? Some sources credit Tesla with the three phase motor (patent filed in 1897) but his patent specified six wires connecting the motor to the generator.? This is not what is used today.? Dolivo-Dobrovolsky a Russian born German working for AEG developed the three phase system now in use along with the delta-wye configuration, the three phase motor (1888), three phase transformer and he designed the first three phase hydroelectric power plant (1891) using all of his developments. ? The split phase or Edison distribution system is part of the single phase system.? The use of the term "multi-phase" is a distortion of facts and implies a three phase system which it is clearly not.? Yes, Edison developed his system for the lights powered by the Pearl Street Station which used a "neutral" and two "hot" conductors.? From one hot conductor to neutral was 110 VDC and across both hot conductors was 220 VDC.? This configuration is still used today but at a slightly higher voltage using AC power but the principle is still valid and Edison still deserves the credit.?? Regards, Jim ? Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy ? ? On Sunday, January 12, 2025 at 08:25:11 PM CST, don Root <drootofallevil@...> wrote: ? ? This is unfortunately a continuation of a part of the off-topic stuff that brings down the respect of our forum, but must be done. Re ??the wording that began in a different topic /g/HallicraftersRadios/message/31466 ?and somehow has been continued in this topic and that continues a dispute is:? ?? “Yes, it is known as the Edison split phase system, see: ” I previously glossed over the above wording believing that a comma was just accidentally missing, and knowing people often use loose wording to express difficult stuff, however when looking at the quoted link, I see the following: ? quote ????? “A split-phase or single-phase three-wire system is a type of distribution. ??It is the (AC) equivalent of the original three-wire ” ? End quote ???and not “Edison split phase system” The term “split-phase” is used frequently in the above link , and ?“Edison” is used twice, but not beside “split-phase” or “split phase”. ? Now, Re?? the previously quoted ? Here is what I see in that quoted text at the top on my bit-machine and screen with my old eyes: Ask An Electrician - How Does Edison 3 Wire (Split Phase) System Work? As I see it , [with? added spaces,color, etc ?for clarity ] the area in dispute says : Edison 3 Wire ???( Split Phase ) ???System. ? I read that in my grammar as: ? Edison 3 Wire ???or ???Split Phase ???System … Which ?means to me that the system can be identified by either ? 1-? ?the term ?“Edison 3 Wire” ??????? ????????or 2-? the term ?“Split Phase” ?? ?????the term ?“single-phase three-wire” is perhaps more clear ?in a multi-phase environment And intentionally misquoting it as ?“Edison split phase system” and then reinforcing it seems to me to be intentionally part of the “misinformation” society that is plaguing this side of the world. ? see
?quote Misinformation is false or inaccurate information—getting the facts wrong. Disinformation is false information which is deliberately intended to mislead—intentionally misstating the facts. The has affected our ability to improve public health, address climate change, maintain a stable democracy, and more. By providing valuable insight into how and why we are likely to believe misinformation and disinformation, psychological science can inform how we protect ourselves against its ill effects. End quote ???
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Jim Whartenby
Donald J
Mike Langner
Jacques_VE2JFE
don Root