Author Topic: What a great site! (Read 2258 times)

Shadow · « **on:** December 12, 2004, 06:43:23 AM »

Hi All, I've been reading this site for three or four months, absorbing as much as I can before starting my first wind generator.I've learned a pile already! But the thing that stands out the most is, What a great site and what a great bunch of people you all are!I always used to think there were. 'Dumb questions', but after following this site for awhile, no-one ever sees any question as a'dumb question' and all are answered accordingly. Its rare to find such a helpful site,and its gonna be nice to know help will be a clik away if I get in over my head. I gotta a couple questions.. more curious than anything, Why was 110/120volt decided on to be the standard?.. Why not 80 volt?..or 100 volt?... Early wind systems were 32 volt.. now we use 12, 24 or 48.. Why is that?... Also has anyone expermented with any sort of free standing tower with 'trolley' system for raising and lowering wind turbine?.Thats my first project at the moment, No climbing towers and no guy wires. Keep up the great work everyone!..And Merry Christmas!

nobicus · « **Reply #1 on:** December 12, 2004, 06:43:43 AM »

I heartily agree. There are some wonderful chaps (and chapesses)who are members of this forum and who give help on help on help.

Can I also add my Christmas greetings to you all.

wdyasq · « **Reply #2 on:** December 12, 2004, 07:23:03 AM »

Well, Nicola Tesla decided on 120/240 volts and 60Hz. I won't try and out guess that fellow.

UL states anything over 50 Volts need their expensive stamp of approval. 12, 24 and 48 Volt systems are unter that arbatrary number and multiples of both 6 and 12 Volts... multiples of standard automotive battery voltages. The 32 volt systems were 16 - 2V cells or 4 - 8 volt batteries. 8 volt bsatteries were common at the time Jacobs mills were being built. Many boats used 32V auxillary systems at that time also. In short, machinery was available in 32V so fewer things needed to be created.

Good luck on your tower.

Ron

jimjjnn · « **Reply #3 on:** December 12, 2004, 07:59:00 AM »

Another thought. As a kid I remember whenRadios and other appliances were listed as ac-dc devices. Where I lived 120 volts dc was the standard. Seems that wall switches were always being replaced and they were huge ! Almost 50% larger and were rotary , ceramic types.

Hose wiring was with 2 asbestos covered wires separated by about 6 inches to 8 inches with "Knob"insulators supporting them every 2-3 feet.

When unplugging an appliance from the wall outlet, there was always an flashing arc. If you got shocked which wasn't uncommon, you really felt it. No circuit breakers,just round screw-in and cartridge fuzes. Fuzes must have been have been good as they are still being manufactured and used to the present day.

ghurd · « **Reply #4 on:** December 12, 2004, 11:13:25 AM »

I for one have considered a trolley tower.

Something like some of the Blue Martin bird house 'appartments' that crank up and down with a boat winch.

Thought of a phone pole for the tower. Should be cheap enough for one that met with a fast car.

Just a pipe dream for where I live. Far to large for here.

Have you seen the tip up towers shown here on the board?

Merry Christmas!

G-

wooferhound · « **Reply #5 on:** December 12, 2004, 01:06:20 PM »

------------

Why was 110/120volt decided on to be the standard?.. Why not 80 volt?..or 100 volt?... ------------

The higher the voltage you have, then the smaller the wire will be

if you are pulling 2400 watts it will be

20 amps at 120 volts and will need 12 gage wire to carry it

or

10 amps at 240 volts and will need 16 gage wire to carry it

Ungrounded Lightning Rod · « **Reply #6 on:** December 12, 2004, 01:19:06 PM »

I always used to think there were. 'Dumb questions', but after following this site for awhile, no-one ever sees any question as a'dumb question' and all are answered accordingly.

It has been said that the only "dumb question" is the one you didn't ask. B-)

There ARE "ignorant questions". But reducing ignorance is the whole POINT of asking and answering questions, isn't it? If it's not an "ignorant question" why was it asked?

Everybody starts out ignorant and has to learn to become informed. Questions are the most focused way to spread information from those who have it to those who don't.

Why was 110/120volt decided on to be the standard?.. Why not 80 volt?..or 100 volt?

I think the standard voltage was picked by Edison for his urban DC system. The higher the better for minimizing the amount of copper you need to ship the power and/or maximizing the distance you can ship it. But if you go too high you get arc-over on the DC generator's commutator.

Tesla got to pick the stepped-up transmission voltages and the frequencies. But I think the delivery voltage was picked to have the same power delivery into resistive loads (incandescent lights, resistive heating appliance) and so "universal motors" (wound rotor, wound field, laminated cores throughout) could be built that would work equally well on either. This let Westinghouse avoid building separate lamps, toasters, and hotplates for his customers and requiring them to convert if they wanted to hook up to his system.

110/115/120 volts was convenient for a number of reasons, besides being a good tradeoff for city-block-scale transport. It's low enough that - AC or DC - it won't automatically kill you if you touch it (though it will if you grab on and may if your skin is wet), jump across even pretty small gaps, or start a persistent arc through a water drop (though it will leak through moist materials or touch it with a metal tool). It's high enough that house wiring is affordable and doesn't waste a lot of power in heating itself. Tube-type radios could rectify it directly and use the resulting voltage for signal processing power without the cost of a voltage-conversion transformer. (Indeed, the "all-american five" five-tube design could run on AC or DC, provided you plugged it in the right way on DC.)

ghurd · « **Reply #7 on:** December 12, 2004, 10:48:20 PM »

And 120 is one of those majic numbers.

It is evenly divisible by 1, 2, 3, 4, 5, 6, 8, 10, 12, etc.

Would make transformers easy?

Stray thought is all...

G-

dalibor · « **Reply #8 on:** December 12, 2004, 11:50:30 PM »

You all probably know that here in europe standard is 220 V 50 Hz. The answer to yours question is in loses which are smaller when using high voltages in transfering electric energy.

Edison was against Tesla in that matter, saying that higher voltages are dangerous to use. He was right, they are dangerous, but whole world is following tesla`s recommendations about it.

Here three-phase voltage is 380 V 50 Hz. What is the value in USA?

greetings from belgrade, serbia

ghurd · « **Reply #9 on:** December 13, 2004, 12:00:36 AM »

Hello to Belgrade!

About 208vac, 60hz. Always 60hz.

Industry gets much higher. Steel mills get 10,400v, maybe even more.

Serbia? It amazes me how people world wide are interested in this topic.

G-

ghurd · « **Reply #10 on:** December 13, 2004, 12:02:40 AM »

Homes usually only get or use 1 phase.

JeroenH · « **Reply #11 on:** December 13, 2004, 04:25:00 AM »

Homes usually only get or use 1 phase.

230V AC 50Hz over here in the Netherlands, although they are gradually increasing it to 240V.

Homes get single phase, but if you use heavy machinery (autoclave, milling equipment etc.) it is possible to get three phase without too much fuss. I think three phase is delivered to normal homes anyway and converted (?) to single phase before entering the house.

drdongle · « **Reply #12 on:** December 13, 2004, 05:12:30 AM »

In Japan they have ( or used to have) a variety of voltages from 100 to 240, thats why a lot of the imported stereo equipment we used to get from there in the 60's had voltage selectors on the back, that was before they made market specific equipment for the US/ UK etc.

Carpe Vigor

Dr.D

JeroenH · « **Reply #13 on:** December 13, 2004, 08:33:04 AM »

thats why a lot of the imported stereo equipment we used to get from there in the 60's had voltage selectors on the back

Thankfully nowadays more and more electronic appliances have multivoltage PSU's working from 100 - 240 V.

SDO · « **Reply #14 on:** December 14, 2004, 07:22:57 AM »

As I recall, DC voltage in the 30+ volt range is likely

to do a real number (meaning screw you up good) on your

joints. I don't know the details, just heard stories

of folks getting DC'ed and never getting over it.

SDO · « **Reply #15 on:** December 14, 2004, 07:26:53 AM »

I'm a believer in the following progress set

unconscious incompetence
conscious incompetence
conscious competence
unconscious competence

Hoping someday in this field to reach #3 and the #4, I'm somewhere

between #2 and #3. The folks on this board and in general the AE

wind folks help without much attitude, which is refreshing indeed.

Thanks to all, and all a good holiday season!

SDO · « **Reply #16 on:** December 14, 2004, 08:05:58 AM »

I would speculate that Michael Jackson would beg to

differ on your TV commentary. Some have said that

he has/had two lifesized blowup dolls in his bedroom

corner. I also heard he enjoys AC over DC, or was

it the other way around

SDO · « **Reply #17 on:** December 14, 2004, 08:24:58 AM »

No question is a dumb question, except one not asked.
DC is more dangerous than AC, at least at the same voltages.
DC can and will mess you up good, joints can get perm damaged.

Its been argued that between 120 and 1800 RPMs is where most

useful work is accomplished. 60 hz produces a motor in single

phase with a nominal speed of 1725 rpm on a 4 pole AC motor.

60 hz AC produces about a 20% smaller transformer than 50 hz.
Although lighting seemed to be without question the real first

use of electricity, the hz decisions were apparently made based

on transformer costs (iron costs and size) as well as usefulness

regarding motors.

NOTE: all this I gleened from the net, so take it with a grain

or electron of salt.

dalibor · « **Reply #18 on:** December 17, 2004, 06:51:14 AM »

its me again. here in serbia every (almost every) house has a three phase electrical instalation. Why is that? dont know, maybe for using thinner electrical wires. for example, some lights are on one phase, others are on the second one. Water heater is on one, oven is on the third etc. i think that it is better comparing to one phase instalation. some folks are having electrical heating for the whole house. it would be very hard to use 24 KW on the single phase.

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Author Topic: What a great site! (Read 2258 times)