ECN Forum Forums Code Related Discussion NEC & other Code issues Hi

Old Appy: Scott is a detailed person, I am sure you have impressed him, you are at the top of your class.
I wanted to see your style of technical writing. It is exactly as I anticipated.
I have always been impressed with the style of expression, used by the residents of the UK, New Zealand, and Australia. They are direct, to the point, and do not use a lot of flourish, to make a statement. I wish I had that literary, and verbal, ability.
Words and statements are usually self explaining, making them easy to understand.
My study of the systems, in your country, indicated a very logical application of technology. I was not aware of the DC transmission line, from the South Island. This is very interesting. I know there is a lot of water on the South Island, I understand there is a lot of hydro plants.
We have a 500 KV, DC line from Oregon to California. It is in sync with the power grid, where supplied, and converted, at each end. I can understand why sync is not necessary in your application.
The cost saving, of the distribution system you have, has a lot of positive qualities.
One transformer bank can supply most domestic and commercial loads. You do not have the loss of neutral problem, inherit in our system.
Voltage drop tolerances, copper consumption, and physical sizes of conductors, are reduced by your technology.
I would like to get a copy of the ampacity ratings of your various wire sizes. I had a chart, but have lost it. Someday we will use metric sizes, it is a very good system.

To add more, concerning my examination of the electrical systems;
I researched statistics concerning the risk difference in using 230 volts to ground, verses 120 volts. I was surprised to see a decrease. I think Old Appy can confirm this fact.
I investigated the cause, and came to the following conclusion;
The countries using 230 volts as the minimum, stress isolation, and insulation, and discourage indiscriminate grounding where not necessary. Essentially they reduce the third lethal path. GFCI requirements are not prevalant. Most wall outlets are switched. What a sensible approach to child proofing.
These countries deal with the cause of a problem, we tend to address the effects, and the problem is not prevented, or corrected.
Now you know how my brain got damaged.

guys;
i'm getting the feeling that we're the only country around on 120V ?



is that true?

Sparky: There is a website somewhere that has the common voltage and frequency of every country in the world. I will try to find it. Anyone out there who knows please jump in. It may be a tourist travel site.
I think you are right, about 120 volts. Most of the American continent, Hawaii, Alaska, and possessions of the US like American Samoa.
British Samoa has 240/415, 50 hertz. I once tried to modify generators to sync with their system. It failed miserably.

We do take extra care ensuring all metalwork in a house or factory is Bonded correctly and grounded to allow a very high fault current path and the opperation of overcurrent protection devices, also circuit breakers are correctly rated for PSCC (you may call it Maximum Fault Current i think

This is another area of interest to me. 230 volts faulting to a grounded object having a fixed resistance will cause a trip more effectively than 120 volts.
Appy, do you still use fuse wire, with different current ratings?
I noticed a lot of copper roofs on houses, is there any special procedures concerning these? Do you have many lightning strikes?
I was there in November, both times I visited. I did not review the weather and climatic conditions.

Not many copper roofs around now days -to expensive. Alot of corrogated iron its not a requirement that i know of to bond a metal roof in a house Althought a person recntly died reaching to the metal roof from a metal swing set to retrieve a tennis ball, the roof had some alterations and a phase conductor had been pierced by a roof nail (live roof) then into a wooden truss with pvc spouting there was no fault current path until the unfortunate incident, Not so much lightning, seem to remember more 20 years ago, alot of rain !!
And we no longer use the porclean fusewire holder (coarse) type of protection many houses still have them, as i do on some circuits, if you add to a circuit that has one of these you must upgrade the circuit breaker We have retro MCB's that fit into the holders. Much Better

Bennie,

There's quite a few Websites with World Power Statistics. Here's a couple:
http://kropla.com/electric2.htm
http://www.clary.com/Service/IntVoltage.asp

Bill

nice links Bill.

the first one will show plugs/receptacles. i wonder if they argue which way is up like we here do??

Appy: I am glad the space station missed your country.
My reference to copper roofs could have been only my assumption. I noticed a lot of green colored roofs. I once flew over The Netherlands and noticed this same thing. I was informed they were copper, that due to weather exposure, were green from oxide formation.
The concept, I noticed while in your country, of not wasting natural resources, maintaining, and protecting equipment was very educational.
I saw a 1931 Ford, Model A pickup, in mint condition, parked in the street in Christchurch. The bed contained sheep shearing tools, it was still being used as a work vehicle. I insulted the owner by saying " beautiful job of restoring", he was irritated and replied "not restored, it has always been in the same condition".
This is not an electrical related message, but may set the stage for explaining some of the reasons for different technology.

[This message has been edited by Bennie R. Palmer (edited 03-23-2001).]