how much current can AWG wire handle

Started by panfilero December 8, 2008
Hello,

Does anyone know where I can find out how much current specific gauges
of wire can handle?  I've looked up web pages on it, but can't figure
out what they mean... for example at

http://www.interfacebus.com/Copper_Wire_AWG_SIze.html

There's a column that says: Current Carrying, and another that says
Fusing Current

I'm interested in figuring out if 20 AWG wire can handle steady DC of
7.25 Amps, for 20 AWG is says
Current Carrying: 1.46
Fusing Current: 58.4

? I don't get what they're saying.... other websites have been
similarly confusing..

Much Thanks

panfilero wrote:

> Hello, > > Does anyone know where I can find out how much current specific gauges > of wire can handle? I've looked up web pages on it, but can't figure > out what they mean... for example at > > http://www.interfacebus.com/Copper_Wire_AWG_SIze.html > > There's a column that says: Current Carrying, and another that says > Fusing Current > > I'm interested in figuring out if 20 AWG wire can handle steady DC of > 7.25 Amps, for 20 AWG is says > Current Carrying: 1.46 > Fusing Current: 58.4 > > ? I don't get what they're saying.... other websites have been > similarly confusing..
Fusing current is pretty obvious isn't it ? Also beware of operation at elevated temperatures and derate when bundled or run in trunking. Graham
> > Does anyone know where I can find out how much current specific gauges > of wire can handle?
www.rstengineering.com then Jim's Engineering Page, then Wire Table.
> > There's a column that says: Current Carrying, and another that says > Fusing Current > > I'm interested in figuring out if 20 AWG wire can handle steady DC of > 7.25 Amps, for 20 AWG is says
# 20 wire can carry any current you like, up to the fusing current. It is all a matter of how hot you are willing to let the wire get. The referenced table above will let you calculate the temperature rise of a wire over ambient for any arbitrary current and gauge.
> Current Carrying: 1.46 > Fusing Current: 58.4 > > ? I don't get what they're saying.... other websites have been > similarly confusing..
The Current Carrying is how much current the wire can handle for a given rise in temperature over ambient. There should also be a note that the temperature rise will be more than calculated if the wires are in a bundle together. An unbundled #20 wire at 7.5 amps will rise about 30F (15C) over ambient, which is pretty warm. Your call. Fusing current is the current at which the wire will melt. Jim
"panfilero"  wrote in message
news:db8f4722-ac23-42b5-8a31-2cc44f7355d5@g38g2000yqn.googlegroups.com...
> Hello, > > Does anyone know where I can find out how much current specific gauges > of wire can handle? I've looked up web pages on it, but can't figure > out what they mean... for example at > > http://www.interfacebus.com/Copper_Wire_AWG_SIze.html > > There's a column that says: Current Carrying, and another that says > Fusing Current > > I'm interested in figuring out if 20 AWG wire can handle steady DC of > 7.25 Amps, for 20 AWG is says > Current Carrying: 1.46 > Fusing Current: 58.4 > > ? I don't get what they're saying.... other websites have been > similarly confusing.. > > Much Thanks
The current carrying capacity in the listed table is based on 700 circular mills per amp, a very conservative number for wire wound inside a transformer where heating is an issue. The National electric code specifies current carrying capacity for open wires or house wiring for example about twice that or 300 to 350 circular mills per amp. This gives 20 AWG wire about a 3 Amp rating. What is your application? What is the duty cycle? What is the thermal environment, how hot can it get? Is it in a transformer or in open air and how insulated? How much voltage drop can you tolerate?
panfilero wrote:
> Hello, > > Does anyone know where I can find out how much current specific gauges > of wire can handle? I've looked up web pages on it, but can't figure > out what they mean... for example at > > http://www.interfacebus.com/Copper_Wire_AWG_SIze.html > > There's a column that says: Current Carrying, and another that says > Fusing Current > > I'm interested in figuring out if 20 AWG wire can handle steady DC of > 7.25 Amps, for 20 AWG is says > Current Carrying: 1.46 > Fusing Current: 58.4 > > ? I don't get what they're saying.... other websites have been > similarly confusing.. > > Much Thanks
Back in the day, the usual rule of thumb for low-frequency power transformers in continuous use was 1000 circular mils per amp, where a 'circular mil' is the square of the diameter in mils (thousandths of an inch), i.e. 1 circular mil = (pi/4) square mil. The 1000 circular mils per amp rule comes out to 5.07e-6 square metres per amp. Cheers, Phil Hobbs
But before the wire gets too hot, there will probably be so much
voltage drop that the voltage at the load is too low, so that might be
the more important criterion.
On Mon, 08 Dec 2008 08:09:02 -0800, panfilero wrote:
> > Does anyone know where I can find out how much current specific gauges of > wire can handle? I've looked up web pages on it, but can't figure out > what they mean... for example at > > http://www.interfacebus.com/Copper_Wire_AWG_SIze.html > > There's a column that says: Current Carrying, and another that says Fusing > Current > > I'm interested in figuring out if 20 AWG wire can handle steady DC of 7.25 > Amps, for 20 AWG is says > Current Carrying: 1.46 > Fusing Current: 58.4 > > ? I don't get what they're saying.... other websites have been similarly > confusing.. > > Much Thanks
You didn't read the rest of the page: "Current Notes: The current shown per wire size listed above is based on 1 amp/ 700 Circular mils, other tables provide different current per wire size, and different current for open air ~ check your local electrical code for the correct current capacity [Ampacity]. The 1 amp/ 700 Circular mils seems to be the most conservative, other sites provide/allow for 1 amp per 200 or 300 Circular mil. For shot wire lengths use 1A/200 Circular mil, for longer wire runs use 300 Circular mil, and for very long wire runs use the table above, 1 amp / 700 Circular mil. The current rating is listed based on permissible voltage drop and not conductor heating. The ability of a wire to carry a given amount of current is affected by a number of additional factors, which are not accounted for in the AWG table above. The ambient temperature of the surrounding air, wire insulation, and number of other wires bundled together [provided below]. Ampacity relates to the ability of the conductor to carry current [amps] before the cable over heats. I understand there are hundreds of Ampacity tables for many different conditions. The numbers above are but one example. Ampacity Tables for many conditions:" Hope This Helps! Rich
"panfilero"

> > I'm interested in figuring out if 20 AWG wire can handle steady DC of > 7.25 Amps, for 20 AWG
** This page say 20AWG is good for 11 amps when used for "chassis wiring" or wires mounted in mid air. http://www.powerstream.com/Wire_Size.htm Tallies with my experience. 1 metre of 20AWG will dissipate about 6 watts at 11 amps when used this way. ..... Phil
On Tue, 9 Dec 2008 09:58:11 +1100, "Phil Allison"
 wrote:

> >"panfilero" > >> >> I'm interested in figuring out if 20 AWG wire can handle steady DC of >> 7.25 Amps, for 20 AWG > > >** This page say 20AWG is good for 11 amps when used for "chassis wiring" or >wires mounted in mid air. > >http://www.powerstream.com/Wire_Size.htm > >Tallies with my experience. > >1 metre of 20AWG will dissipate about 6 watts at 11 amps when used this way. > > > >..... Phil >
AC 43.13-1B shows AWG 20 okay for about 16.5A if you don't mind 80�C rise (eg. very high temperature rated insulation in moderate ambient). That's for *one wire in free air*, deratings for bundles (two wires are a bundle), and altitude, of course, and the detailed calculations are shown for various situations. May be available on the FAA dot GOV website. Mostly you'll not want to get anywhere near those current levels or voltage drop will kill you.
On Mon, 08 Dec 2008 23:21:44 -0000, Spehro Pefhany
 wrote:

> On Tue, 9 Dec 2008 09:58:11 +1100, "Phil Allison" > wrote: > >> >>"panfilero" >> >>> >>> I'm interested in figuring out if 20 AWG wire can handle steady DC of >>> 7.25 Amps, for 20 AWG >> >> >>** This page say 20AWG is good for 11 amps when used for "chassis wiring" or >>wires mounted in mid air. >> >>http://www.powerstream.com/Wire_Size.htm >> >>Tallies with my experience. >> >>1 metre of 20AWG will dissipate about 6 watts at 11 amps when used this way. >> >> >> >>..... Phil >> > AC 43.13-1B shows AWG 20 okay for about 16.5A if you don't mind 80�C > rise (eg. very high temperature rated insulation in moderate ambient). > > That's for *one wire in free air*, deratings for bundles (two wires > are a bundle), and altitude, of course, and the detailed calculations > are shown for various situations. May be available on the FAA dot GOV > website. > > Mostly you'll not want to get anywhere near those current levels or > voltage drop will kill you.
How can a voltage drop kill someone? The lower the voltage at the outlet, the safer it is! -- http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com Your cancellation is being cancelled. Please press ok to continue cancelling the cancellation or cancel to cancel cancelling the cancellation.
On Wed, 17 Dec 2008 02:22:20 -0000, Archimedes' Lever
 wrote:

> On Tue, 16 Dec 2008 18:48:50 -0000, "Peter Hucker" wrote: > >> >>Line length is nothing to do with sig delimiters. One is a guideline, the other
is a command to strip the text below.
> > > Dumbass. The remark was about how stupid you are about line length, > yet you want us all to believe you have brains because your retarded ass > decided to get a grasp of how a sig works. > > A: You ARE utterly retarded about line length. > > and > > B: We all already know that you do not possess any brains, much less > intelligence, so you can stop trying to impress folks. > > That is aside from the fact that the material you choose to 'impress > us' with further proves just how stupid you are.
You are worse than Ian at trolling. At least he doesn't tend to repeat himself. -- http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com "It was reported last week that a citizen's group is trying to remove porn channels from hotels across the country." "The group is called the Coalition of People Who Want to Ruin Everything."
On Sun, 14 Dec 2008 08:04:08 -0800, Archimedes' Lever
 wrote:

>On Sun, 14 Dec 2008 14:13:15 +0000 (GMT), Stuart >wrote: > >>no-one can be bothered to >>say millimetres every time you want to pass someone a dimension. > > > Lazy fucking retards. > > You do not say 'cent' for centimeter, or 'dec' for decimeter, and I use >both terms in my use of the metric system. > > You guys are goddamned idiots considering that the rest of the world >makes considerations for your weights and measures systems, yet you >refuse to make any accommodations for those of others. > > I am quite sure that there are far more intelligent folk over there than >the likes of you, asswipe.
When WILL you learn to spell properly? it's ARSEWIPE, you dullard!
On Sun, 14 Dec 2008 08:04:30 -0800, Archimedes' Lever
 wrote:

>On Sun, 14 Dec 2008 14:13:15 +0000 (GMT), Stuart >wrote: > >>Continental europe has been metric for so long I doubt they would even >>recognise the term the way you use it. >> >>Stuart > > > You're a fucking idiot.
And you're a swivel-eyed lunatic. So there!
On Tue, 16 Dec 2008 18:48:50 -0000, "Peter Hucker"  wrote:

> >Line length is nothing to do with sig delimiters. One is a guideline, the other is
a command to strip the text below. Dumbass. The remark was about how stupid you are about line length, yet you want us all to believe you have brains because your retarded ass decided to get a grasp of how a sig works. A: You ARE utterly retarded about line length. and B: We all already know that you do not possess any brains, much less intelligence, so you can stop trying to impress folks. That is aside from the fact that the material you choose to 'impress us' with further proves just how stupid you are.
On Tue, 16 Dec 2008 06:31:42 -0000, Archimedes' Lever
 wrote:

> On Wed, 10 Dec 2008 17:55:42 -0000, "Peter Hucker" wrote: > >> >>If you don't like the sigs, ignore them. That's what the delimiter is for. > > Coming from an absolute Usenet retard that doesn't even know what the > line length is... That's rich.
Line length is nothing to do with sig delimiters. One is a guideline, the other is a command to strip the text below.
> You are dumber than a beached whale carcass. Beached and dead is pretty > damned dumb, boy.
Are you competing with Terrell the troll? -- http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com Why do men find it difficult to make eye contact? Breasts don't have eyes.
On Tue, 16 Dec 2008 04:08:51 -0000, krw  wrote:

> In article , none@spam.com > says... >> On Sun, 14 Dec 2008 23:31:20 -0000, krw wrote: >> >> > In article , none@spam.com >> > says... >> >> On Sun, 14 Dec 2008 05:08:38 -0000, krw wrote: >> >> >> >> > In article , none@spam.com >> >> > says... >> >> >> On Sat, 13 Dec 2008 00:38:33 -0000, krw wrote: >> >> >> >> >> >> > In article , none@spam.com >> >> >> > says... >> >> >> >> On Fri, 12 Dec 2008 23:55:44 -0000, krw wrote: >> >> >> >> >> >> >> >> > In article , none@spam.com >> >> >> >> > says... >> >> >> >> >> On Fri, 12 Dec 2008 23:45:57 -0000, Michael A. Terrell
wrote:
>> >> >> >> >> >> >> >> >> >> > >> >> >> >> >> > Peter Hucker wrote: >> >> >> >> >> >> >> >> >> >> >> >> On Fri, 12 Dec 2008 23:33:49 -0000, Michael A. Terrell
wrote:
>> >> >> >> >> >> >> >> >> >> >> >> > >> >> >> >> >> >> > Peter Hucker wrote: >> >> >> >> >> >> >> >> >> >> >> >> >> >> On Fri, 12 Dec 2008 19:18:11 -0000, Sjouke Burry
wrote:
>> >> >> >> >> >> >> >> >> >> >> >> >> >> > Rich Grise wrote: >> >> >> >> >> >> >> >> On Wed, 10 Dec 2008 18:32:54 +0000, Peter Hucker wrote: >> >> >> >> >> >> >> >>> Mil is confusing. A lot of folk in metric countries say
"mil" short for
>> >> >> >> >> >> >> >>> millimetre. >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> Wrong. A mil is 0.001 inch (short for milli-inch); metric
countries would
>> >> >> >> >> >> >> >> have no reason to use it. >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> Thanks, >> >> >> >> >> >> >> >> Rich >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> > Wrong. Being in a metric country mil means millimeter. >> >> >> >> >> >> >> >> >> >> >> >> >> >> Some day the US will catch up with the rest of us? >> >> >> >> >> >> > >> >> >> >> >> >> > >> >> >> >> >> >> > That would be like getting an STD, just to prove you can. >> >> >> >> >> >> >> >> >> >> >> >> You object to the metric system? [scoffs] >> >> >> >> >> > >> >> >> >> >> > >> >> >> >> >> > Small minds always scoff. >> >> >> >> >> >> >> >> >> >> I take it back, you are even more childish than Ian Field. You can
sit next to him in my killfile. Go snuggle up, you'll get on well together.
>> >> >> >> >> >> >> >> >> > Says the idiot limey who doesn't even know how to set up his >> >> >> >> > newsreader. >> >> >> >> >> >> >> >> My newsreader works just fine. Any problems you are experiencing are up
your end.
>> >> >> >> >> >> >> > No, dumbass, you are simply too stupid to realize you're phucked up. >> >> >> >> >> >> You haven't even stated the problem you're having. That's like putting
your car into a garage and saying it's broken.
>> >> >> >> >> > I certainly have, though you're obviously too stupid to remember. >> >> >> >> The only thing you've said in the last month is that up there: "Says the idiot
limey who doesn't even know how to set up his newsreader."
>> > >> > Like I said, you're a stupid Brit and can't be expected to >> > understand. Hint: Your line length is phucked up. Of course being >> > a stupid, arrogant, Brit, you don't care. >> >> http://www.hucker.plus.com/temp/notepad.jpg >> >> This can do it, in fact it could do it in Windows 3. Update your newsreader. > > You've simply proved that you are a stupid, arrogant Brit.
And you're an out of date American geek. -- http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com Why is Michael Jackson's album entitled "Bad?" Because he couldn't spell "Pathetic."
On Wed, 10 Dec 2008 17:55:42 -0000, "Peter Hucker"  wrote:

> >If you don't like the sigs, ignore them. That's what the delimiter is for.
Coming from an absolute Usenet retard that doesn't even know what the line length is... That's rich. You are dumber than a beached whale carcass. Beached and dead is pretty damned dumb, boy.
In article , none@spam.com 
says...
> On Sun, 14 Dec 2008 23:31:20 -0000, krw wrote: > > > In article , none@spam.com > > says... > >> On Sun, 14 Dec 2008 05:08:38 -0000, krw wrote: > >> > >> > In article , none@spam.com > >> > says... > >> >> On Sat, 13 Dec 2008 00:38:33 -0000, krw wrote: > >> >> > >> >> > In article , none@spam.com > >> >> > says... > >> >> >> On Fri, 12 Dec 2008 23:55:44 -0000, krw wrote: > >> >> >> > >> >> >> > In article , none@spam.com > >> >> >> > says... > >> >> >> >> On Fri, 12 Dec 2008 23:45:57 -0000, Michael A. Terrell
wrote:
> >> >> >> >> > >> >> >> >> > > >> >> >> >> > Peter Hucker wrote: > >> >> >> >> >> > >> >> >> >> >> On Fri, 12 Dec 2008 23:33:49 -0000, Michael A. Terrell
wrote:
> >> >> >> >> >> > >> >> >> >> >> > > >> >> >> >> >> > Peter Hucker wrote: > >> >> >> >> >> >> > >> >> >> >> >> >> On Fri, 12 Dec 2008 19:18:11 -0000, Sjouke Burry
wrote:
> >> >> >> >> >> >> > >> >> >> >> >> >> > Rich Grise wrote: > >> >> >> >> >> >> >> On Wed, 10 Dec 2008 18:32:54 +0000, Peter Hucker wrote: > >> >> >> >> >> >> >>> Mil is confusing. A lot of folk in metric countries say
"mil" short for
> >> >> >> >> >> >> >>> millimetre. > >> >> >> >> >> >> >> > >> >> >> >> >> >> >> Wrong. A mil is 0.001 inch (short for milli-inch); metric
countries would
> >> >> >> >> >> >> >> have no reason to use it. > >> >> >> >> >> >> >> > >> >> >> >> >> >> >> Thanks, > >> >> >> >> >> >> >> Rich > >> >> >> >> >> >> >> > >> >> >> >> >> >> > Wrong. Being in a metric country mil means millimeter. > >> >> >> >> >> >> > >> >> >> >> >> >> Some day the US will catch up with the rest of us? > >> >> >> >> >> > > >> >> >> >> >> > > >> >> >> >> >> > That would be like getting an STD, just to prove you can. > >> >> >> >> >> > >> >> >> >> >> You object to the metric system? [scoffs] > >> >> >> >> > > >> >> >> >> > > >> >> >> >> > Small minds always scoff. > >> >> >> >> > >> >> >> >> I take it back, you are even more childish than Ian Field. You can
sit next to him in my killfile. Go snuggle up, you'll get on well together.
> >> >> >> >> > >> >> >> > Says the idiot limey who doesn't even know how to set up his > >> >> >> > newsreader. > >> >> >> > >> >> >> My newsreader works just fine. Any problems you are experiencing are up
your end.
> >> >> >> > >> >> > No, dumbass, you are simply too stupid to realize you're phucked up. > >> >> > >> >> You haven't even stated the problem you're having. That's like putting your
car into a garage and saying it's broken.
> >> >> > >> > I certainly have, though you're obviously too stupid to remember. > >> > >> The only thing you've said in the last month is that up there: "Says the idiot
limey who doesn't even know how to set up his newsreader."
> > > > Like I said, you're a stupid Brit and can't be expected to > > understand. Hint: Your line length is phucked up. Of course being > > a stupid, arrogant, Brit, you don't care. > > http://www.hucker.plus.com/temp/notepad.jpg > > This can do it, in fact it could do it in Windows 3. Update your newsreader.
You've simply proved that you are a stupid, arrogant Brit. -- Keith
On Sun, 14 Dec 2008 23:31:20 -0000, krw  wrote:

> In article , none@spam.com > says... >> On Sun, 14 Dec 2008 05:08:38 -0000, krw wrote: >> >> > In article , none@spam.com >> > says... >> >> On Sat, 13 Dec 2008 00:38:33 -0000, krw wrote: >> >> >> >> > In article , none@spam.com >> >> > says... >> >> >> On Fri, 12 Dec 2008 23:55:44 -0000, krw wrote: >> >> >> >> >> >> > In article , none@spam.com >> >> >> > says... >> >> >> >> On Fri, 12 Dec 2008 23:45:57 -0000, Michael A. Terrell
wrote:
>> >> >> >> >> >> >> >> > >> >> >> >> > Peter Hucker wrote: >> >> >> >> >> >> >> >> >> >> On Fri, 12 Dec 2008 23:33:49 -0000, Michael A. Terrell
wrote:
>> >> >> >> >> >> >> >> >> >> > >> >> >> >> >> > Peter Hucker wrote: >> >> >> >> >> >> >> >> >> >> >> >> On Fri, 12 Dec 2008 19:18:11 -0000, Sjouke Burry
wrote:
>> >> >> >> >> >> >> >> >> >> >> >> > Rich Grise wrote: >> >> >> >> >> >> >> On Wed, 10 Dec 2008 18:32:54 +0000, Peter Hucker wrote: >> >> >> >> >> >> >>> Mil is confusing. A lot of folk in metric countries say "mil"
short for
>> >> >> >> >> >> >>> millimetre. >> >> >> >> >> >> >> >> >> >> >> >> >> >> Wrong. A mil is 0.001 inch (short for milli-inch); metric
countries would
>> >> >> >> >> >> >> have no reason to use it. >> >> >> >> >> >> >> >> >> >> >> >> >> >> Thanks, >> >> >> >> >> >> >> Rich >> >> >> >> >> >> >> >> >> >> >> >> >> > Wrong. Being in a metric country mil means millimeter. >> >> >> >> >> >> >> >> >> >> >> >> Some day the US will catch up with the rest of us? >> >> >> >> >> > >> >> >> >> >> > >> >> >> >> >> > That would be like getting an STD, just to prove you can. >> >> >> >> >> >> >> >> >> >> You object to the metric system? [scoffs] >> >> >> >> > >> >> >> >> > >> >> >> >> > Small minds always scoff. >> >> >> >> >> >> >> >> I take it back, you are even more childish than Ian Field. You can sit
next to him in my killfile. Go snuggle up, you'll get on well together.
>> >> >> >> >> >> >> > Says the idiot limey who doesn't even know how to set up his >> >> >> > newsreader. >> >> >> >> >> >> My newsreader works just fine. Any problems you are experiencing are up
your end.
>> >> >> >> >> > No, dumbass, you are simply too stupid to realize you're phucked up. >> >> >> >> You haven't even stated the problem you're having. That's like putting your
car into a garage and saying it's broken.
>> >> >> > I certainly have, though you're obviously too stupid to remember. >> >> The only thing you've said in the last month is that up there: "Says the idiot
limey who doesn't even know how to set up his newsreader."
> > Like I said, you're a stupid Brit and can't be expected to > understand. Hint: Your line length is phucked up. Of course being > a stupid, arrogant, Brit, you don't care.
http://www.hucker.plus.com/temp/notepad.jpg This can do it, in fact it could do it in Windows 3. Update your newsreader. -- http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com Two men are approaching each other on a sidewalk. Both are dragging their right foot as the walk. As they meet, one man looks at the other knowingly, points at his foot and says, "Vietnam, 1969." The other hooks his thumb behind him says, "Dog shit, 20 feet back."
� "Stuart" 
������
���
������ 
news:500dc68696Spambin@argonet.co.uk...
> In article , > Jamie wrote: >> Interesting, we have 250Kwatt 100khz oscillators that require 260 amps @ >> 12V ac to warm up the fil.. and put -15VkDC cathode voltage from a 3 >> phase SCR driving supply, we're good to go.! > > The original valves in those transmitters (CAT29 triodes in push-pull > class C for the final) had pure tungsten filaments running at 20V DC. By > the time I saw them they had CAT30s with thioriated (sp?) tungsten and > were fed at 9V. Same MG set, just lower field current. IIRC the filament > generators were capable of 2000A. DC was used to avoid hum modulation of > the output and the polarity was reversed every week. Later transmitters > used AC fills, usually two phase derived by Scott connection of the supply > transformers. > > The last HF transmitters I worked on before moving on to "domestic > services" were Marconi 300kW using a single Thomson Tetrode for the output > - Hypervapourtron (tm) cooling and Pyroblock (tm) grid. Apart from the > output valve pretty well everything was solid state, including the 25kV > rectifier stack. >
A 300 MW brown coal unit which I visited in Kozani (east Macedonia-area of Greece, not the country) had a shunt DC generator, for the excitation of the alternator. It was 220 V, 1000 A, and had brushes the size of bricks. The alternator's output was 21 kV, 10 kA with special aluminium rails going directly to the unit's transformer, where they were upped to 400 kV, 400 A for transmission to Athens. -- Tzortzakakis Dimitrios major in electrical engineering mechanized infantry reservist hordad AT otenet DOT gr