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History of 600/347v?

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tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Do any of you northerners know the history of 600/347v in Canada? Why was this voltage picked?
I know some early US systems in New England were 550 Volts, and street cars in the eastern US were (still are?) 600V.
Just like our North Americian 208V I don't think 600V was/is used anywhere else.

Cheers
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
I think all early systems were based on educated guesses of engineers trying to juggle voltages vs currents.
 
Which came first, the 600v system or the 600v equipment and conductor insulation system? I can see wanting your equipment to run at it's max voltage rating for economy.

I've seen a few 600v systems in Rhode island in old Mills. Ungrounded though not wye.
 

Hv&Lv

Senior Member
Location
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Occupation
Engineer/Technician
You had to start somewhere...
If there wasn’t power anywhere, and a competitor started 110DC, another man was working on AC110, and you were an opportunistic businessman, what would you do?
I would build a generation plant and offer a voltage that happened to match the voltages my appliances offered..yes, I’m building appliances also.
REA offered a standard voltage package around the country of 230V when they were electrifying the country.
 

jim dungar

Moderator
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Wisconsin
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PE (Retired) - Power Systems
When looking at historical voltage values, remember that what we consider normal now has not always been that way.

For example, the nominal original voltages were 440V/220V/110V. These were then upgraded to the 460/230/115 that many of our mentors grew up with. For the past 50 years, or so, we have been using the familiar 480/240/120V.

Compare these voltage increase to the 550 and 600V systems and you will notice a similar percentage increase over the years.
 

Hv&Lv

Senior Member
Location
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Occupation
Engineer/Technician
Also remember the nomenclature has changed over the years..
service voltage, utilization voltage, nominal, nameplate...
460/230/115 is nameplate.

480/240/120 is nominal
It’s the same bank
 

tom baker

First Chief Moderator & NEC Expert
Staff member
Location
Bremerton, Washington
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Master Electrician
I did some classes at a local Weyerhaeuser mill that fromthe 1920s, maintenance staff said they used 600 volt as it was the highest voltage they could use with out going to MV
 
When looking at historical voltage values, remember that what we consider normal now has not always been that way.

For example, the nominal original voltages were 440V/220V/110V. These were then upgraded to the 460/230/115 that many of our mentors grew up with. For the past 50 years, or so, we have been using the familiar 480/240/120V.

FWIW, I just spent some time in a 1948 American Electrician's Handbook- the voltage tables had separate columns for "generators and energy-delivering apparatus" and "motors and energy-utilization apparatus" with numbers like 120/208 in the first and 110 in the second (or 600/550 on another row). No suggestions on why 240/480/600 here. Also checked a 1914 American Handbook for Electrical Engineers, nothing that I could easily find (it's 1800 pages!!), but 600v AC is included.

I suspect that 600v AC was an offshoot of 600v DC (local railways) and it seemed high enough to be useful but low enough to not need special wiring & equipment.
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
... 1948 American Electrician's Handbook- ... No suggestions on why 240/480/600 here. Also checked a 1914 American Handbook for Electrical Engineers, nothing that I could easily find (it's 1800 pages!!), but 600v AC is included.

I don't think the nominal voltage were raised to the 480V level until the 50-60's time frame. My Handbook foe Electrical Engineers, from 1969, talks about 480V 3-phase and 115/230V single phase. But, its NEC refence for motor full load amps has column headings of 110/220/440/550V.
 
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tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Wow thanks all for the replies, yeah is suppose it is a descendant of the old 550V, its still curious why did all of Canada go for 600/347V and skip 480/277?
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
You had to start somewhere...
If there wasn’t power anywhere, and a competitor started 110DC, another man was working on AC110, and you were an opportunistic businessman, what would you do?
I would build a generation plant and offer a voltage that happened to match the voltages my appliances offered..yes, I’m building appliances also.
REA offered a standard voltage package around the country of 230V when they were electrifying the country.

How did we get stuck with 120? Its like everyone knew 220 was better, but some conspiracy kept us on 110 volts.
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
How did we get stuck with 120? Its like everyone knew 220 was better, but some conspiracy kept us on 110 volts.
It’s where we ended up...
As a whole we still push the upper limits. Many utilities run their regs at 123V-125V
“Everyone” is quite a broad statement.
Other countries have voltage nominals like 110,115,120, even 127.
With all the electronics available today, the switch mode power supplies like the lower voltages anyway. Less losses to get to 5V
 

drcampbell

Senior Member
Location
The Motor City, Michigan USA
Occupation
Registered Professional Engineer
How did we get stuck with 120? Its like everyone knew 220 was better, but some conspiracy kept us on 110 volts.
If my understanding of the folk legend is correct, the very first light bulbs were designed to run on 100 volts because ... why not? It's a nice round number. And generators were adjusted to put out 110 volts, to compensate for voltage drop. 220 came later, as part of a 110-220 Edison circuit, when it was discovered that wiring even a relatively small zone such as a city block on such a low voltage required staggering amounts of copper.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
It’s where we ended up...
As a whole we still push the upper limits. Many utilities run their regs at 123V-125V
“Everyone” is quite a broad statement.
Other countries have voltage nominals like 110,115,120, even 127.
With all the electronics available today, the switch mode power supplies like the lower voltages anyway. Less losses to get to 5V


Most of the world is 230 volts today, and even back in the day half the world was 220v.
 
It would be interesting to know where in the USA 600/347 was/is available. To that end, AFAICT PG&E (Northern California) probably never offered 600/347 (although their Green Book mentions both 2-phase and DC service for existing customers).
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
Most of the world is 230 volts today, and even back in the day half the world was 220v.
So why did THEY change “back in the day”?

It has to do more with standardizing to neighbors, convenience and what’s available rather than any real hard and fast answer.

our neighbors use 110-120. Canada, Mexico, Belize, Cuba, the islands...Brazil is a mix...

Europe is more 220 after they standardized for convenience. Not because one is necessarily better.

admittedly, if your stringing wire through a neighborhood at 220 vs 120 then 220 is better. Some places do that. VD is rampant in those areas..(...wait for it...)

where we have transformers about every house or couple of houses it isn’t a big deal.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
So why did THEY change “back in the day”?

It has to do more with standardizing to neighbors, convenience and what’s available rather than any real hard and fast answer.

our neighbors use 110-120. Canada, Mexico, Belize, Cuba, the islands...Brazil is a mix...

Europe is more 220 after they standardized for convenience. Not because one is necessarily better.

admittedly, if your stringing wire through a neighborhood at 220 vs 120 then 220 is better. Some places do that. VD is rampant in those areas..(...wait for it...)

where we have transformers about every house or couple of houses it isn’t a big deal.


More efficient. A transformer every couple of homes is impractical energy wise.
 
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