- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
Most utilities do not follow this standard nomenclature. But those of us that depend on the NEC should.
Voltage Ratings: 110/115/120, 220/230/240 or 440/460/480
- Thread starter Jraef
- Start date
JakupstateNY
Member
- Location
- Ny
- Occupation
- Semi retired
Learning daily, thank you
TX+ MASTER#4544
Senior Member
- Location
- Texas
- Occupation
- electrical Code instructor and mentor
drcampbell said....
I'm still laughing at ".....hold my beer and watch this" That was funny!
I'm sure you were referring to the three squiggly lines, coils.
Now, show me a corner grounded transformer......and the voltage at the corner.
Then have another one on me.
As a certain poster often says.....cheers.
Thanks for the humor.
Comments accepted.
TX+MASTER#4544
I'm still laughing at ".....hold my beer and watch this" That was funny!
I'm sure you were referring to the three squiggly lines, coils.
Now, show me a corner grounded transformer......and the voltage at the corner.
Then have another one on me.
As a certain poster often says.....cheers.
Thanks for the humor.
Comments accepted.
TX+MASTER#4544
kingpb
Senior Member
- Location
- SE USA as far as you can go
- Occupation
- Engineer, Registered
But in the end, people will still call it 120/208, and 277/480. And every time the drawings saw 120/208V, I I know they mean 208Y/120V will issue a Change order.
The great thing about standards is that there are so many to choose from.What an absolute bloody mess....................................
Tom Horne
Not so much in Europe. Residential is 230Vac. Industrial is 400/230V. There are specials, for example in Paper Mills, so obviously they are not standards
I'm sure that you are aware that we were discussing the variations in North American service delivery voltages. Just because Europe got it's collective act together doesn't change the plethora of voltages used in delivering power to premises on this continent. Europe's distribution development had the advantage of the mistakes that had been made earlier in the development of the North American systems. As is often true the competitive rush to be early to market caused North American investor owned utility ventures to make mistakes that still cause problems today.
I believe that the Multi-Grounded Neutral of most North American distribution systems is a good example of one of those errors in fundamental design. The stray current problems that continue today cause illness and production losses in domesticated animal live stock. More importantly such stray neutral currents are a major contributor to fresh water paralytic drowning deaths.
For all I know Multi-Grounded Neutral systems may also be in use in Europe but the additional characteristic of the North American multi-grounded neutral system is that the neutral is common to both the Distribution and Secondary Distribution systems. By that I mean that the same neutral is connected to both windings of the Secondary Distribution transformers. That practice allows primary distribution currents to flow into the earth at any of the grounding points in the distribution system, including those located on private premises. The well documented effects of those stray currents on dairy production alone is enough to demonstrate the stray current effects of a multi-grounded AND Distribution and delivery common neutral system. I would benefit from a new thread on how neural currents of both voltage sets are handled in Europe. Perhaps others would to.
There are still a few places in North America were the delivered voltage is 100 volts DC. Admittedly those are mostly tiny island communities were the power system was originally privately owned shared generation for vacation homes of the wealthy but the fact that several such systems still exist is an example of how diverse North American service voltages are.
The principle reason that the service voltage in many places rose from 100 volts to 110 volts was that Edison's initial DC power plant ran on the standard telegraph outside line voltage of the time which was 100 volts. Designs for the Dynamos used to produce larger amounts of 100 volt DC were already in production and readily available for those DC distribution systems. Edison already had a number of patents on improvements to telegraphy technology which allowed up to 4 signals on a single telegraph wire. Since he was first out of the gate with a public electrical system he turned to what he was already familiar with from his work in telegraphy. As use increased, and electric lighting began displacing gas lights, the Manhattan electrical system began to become overloaded. To avoid the expense of constructing additional distribution wiring Edison raised the voltage in order to deliver more watts at the existing current capacity of his Manhattan outside plant distribution system. With a great many premise electrical systems then at the limit of the insulation materials used in the earlier installations further increases in voltages higher than 110 volts for DC systems were not practical. When the "current war" ended with the defeat of Edison's DC distribution by Westinghouse's, Tesla invented, AC power the installation of new DC systems came to a virtual halt with only a few existing systems remaining as built. Many of the earlier DC systems were eventually converted to AC. The increase in the service voltage to 120/240 1Ø was again the result of use increasing faster than the expansion of electrical distribution systems. With the reduction of the arcing inherent in DC switching the voltage delivered to customer premises could be raised again to its present 120/240 volts. That is all fairly well documented electrical history but it doesn't explain the wildly different distribution voltage systems.
Tom Horne
I believe that the Multi-Grounded Neutral of most North American distribution systems is a good example of one of those errors in fundamental design. The stray current problems that continue today cause illness and production losses in domesticated animal live stock. More importantly such stray neutral currents are a major contributor to fresh water paralytic drowning deaths.
For all I know Multi-Grounded Neutral systems may also be in use in Europe but the additional characteristic of the North American multi-grounded neutral system is that the neutral is common to both the Distribution and Secondary Distribution systems. By that I mean that the same neutral is connected to both windings of the Secondary Distribution transformers. That practice allows primary distribution currents to flow into the earth at any of the grounding points in the distribution system, including those located on private premises. The well documented effects of those stray currents on dairy production alone is enough to demonstrate the stray current effects of a multi-grounded AND Distribution and delivery common neutral system. I would benefit from a new thread on how neural currents of both voltage sets are handled in Europe. Perhaps others would to.
There are still a few places in North America were the delivered voltage is 100 volts DC. Admittedly those are mostly tiny island communities were the power system was originally privately owned shared generation for vacation homes of the wealthy but the fact that several such systems still exist is an example of how diverse North American service voltages are.
The principle reason that the service voltage in many places rose from 100 volts to 110 volts was that Edison's initial DC power plant ran on the standard telegraph outside line voltage of the time which was 100 volts. Designs for the Dynamos used to produce larger amounts of 100 volt DC were already in production and readily available for those DC distribution systems. Edison already had a number of patents on improvements to telegraphy technology which allowed up to 4 signals on a single telegraph wire. Since he was first out of the gate with a public electrical system he turned to what he was already familiar with from his work in telegraphy. As use increased, and electric lighting began displacing gas lights, the Manhattan electrical system began to become overloaded. To avoid the expense of constructing additional distribution wiring Edison raised the voltage in order to deliver more watts at the existing current capacity of his Manhattan outside plant distribution system. With a great many premise electrical systems then at the limit of the insulation materials used in the earlier installations further increases in voltages higher than 110 volts for DC systems were not practical. When the "current war" ended with the defeat of Edison's DC distribution by Westinghouse's, Tesla invented, AC power the installation of new DC systems came to a virtual halt with only a few existing systems remaining as built. Many of the earlier DC systems were eventually converted to AC. The increase in the service voltage to 120/240 1Ø was again the result of use increasing faster than the expansion of electrical distribution systems. With the reduction of the arcing inherent in DC switching the voltage delivered to customer premises could be raised again to its present 120/240 volts. That is all fairly well documented electrical history but it doesn't explain the wildly different distribution voltage systems.
Tom Horne
European systems have developed over many years and now, in a few decades, it has been rationalised and simpler. Can you same for USA?
No! I thought it was clear that I was saying the exact opposite. I've not studied European electrical distribution practices in any depth but at first blush the European system appears to be harmonized to a great degree. The North American system appears to me to be in a great deal of disarray. I sincerely did not mean any disrespect to you or the European system. I was, however inadequately, trying to express my admiration of the degree of standardization Europe seems to have developed in many areas of technology, not to mention commerce, currency...
Tom Horne
- Location
- New Jersey
- Occupation
- Journeyman Electrician
I took it as you meant the opposite as well. I don't find the US standards to be completely lacking. We do have several standard nominal voltage systems. I find the use of the 230 volt motor voltage to be confusing. It is okay for 208, what about 240? We don't use 230 volt systems so is it neither or both ?
I'm have a few changes in my life here in UK - I'm 77 years old. We used to have currency in pounds in shillings and pence. We fixed that with decimal currency, much simpler. Then we got metric units (more accurately System International). Now we have kilos rather than pounds and ounces. Again, it is simpler. But there are still people who want old units - go to a pub and get a pint of beer but have a wine and get 250 ml
Enough...........
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Hope you don't take this wrong but it might be time to consider being concise and to the point instead of typing a short story that's hard to read and follow.
The voltage on the name plate of any NEMA rated load is +- 10% so at 230 volts you can go up to 253 volts and down to 207 volts. That means that the allowable range of voltages is 207 to 253. So it does indeed cover all of the commonly delivered service voltages to residences. Thus the answer is BOTH.
Tom Horne