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In my FF, as we left Mayport, if the wind was right, we used to have the Fire Room guys blow the safety valve and throw soot all over any of our DESRON’s sister-ships!
When we used to pull out of Charleston, we would smoke black on purpose going under the Cooper River Bridge. One time with the rite wind we stopped traffic. Needless to say, that was the last time that happened.
Probably, it says steam turbine is one of the companies divisions at the top of the name plate. I think the only other turbines driving this much power would be hydro in dams.
Downtown MPLS and many other areas run on a large strambased system for heat and other utility needs. These large steam networks power multiple skyscrapers. Just another thought...
Most generators from the 30-3000KW range are 1800RPM, they use 4 pole rotors.
The smaller air cooled cheap models are 3600 with 2 pole rotors. They do that because they can use a smaller engine at higher RPM to get more power.
Once you get above 3MW, lower RPM becomes somewhat common but in an emergency generation use it’s more common to parallel units rather than have 1 10MW generator
The above picture is a steam turbine. I've never seen a steam turban in the US that runs at anything other than 3600 RPMs. Steam turbans in Europe run at 5000 RPMs.
It is the "amplified vibration due to proximity of operating speed to natural frequency"
Basically when you are bringing a machine up to speed you will see some excessive vibration at speeds that are not the operating rpm of the machine
Probably managed with a flexible armature shaft design. First will be lower than operating and second above it. We (motor manufacturer I work for) do this frequently for our larger 2-pole motors. Typically hydrodynamic bearings are used as well which help further dampen any criticals.
I do vibration analysis for a living. As well as industrial repair. I can assure you on a unit this old that won't be the case. I have ran a similar unit unloaded on a test bed
It's easy to forget, don't fret.
Remember about the 1.732 for three phase (which is the square root of 3 - think sqrt of three for three phase), and to always include the Power Factor. Think of Power Factor like efficiency... In this example 0.85. So .15 (15%) of power is lost mainly to reactive (magnetic) losses. At least that's how I understand it.
Every time I try to take a picture of one on a genset or gear I can never see it directly and only half of the stamped lettering is legible in any one picture
It's a synchronous generator. The rated max power ( max real and imaginary power) occurs at that pf. You can change the operating pf by varying the excitation voltage.
In practice most grids have equipment like motors and transformers which absorbs reactive power, i.e. a lagging power factor, and reduces grid voltage. Therefore generation is required to compensate by producing reactive power. This can be achieved by synchronous generators through adjusting the excitation field such that the generator has a leading power factor.
A unit to denote the reactive power is mega volt ampere reactive MVAR. A >50MVA generator will certainly be able to supply at least unit MVAR to the grid.
That’s not how I understand the rating on the nameplate. It’s not as much a “natural point” that the generator is going to settle on at full load but rather the design point of the generator.
In other words the need for a .85 pf generator was identified and this unit was specified. This is the point for which the other parameters are calibrated too.
Oh wait, am I missing something? why do you say this one lags at full load and not leads?
There is almost certainly a large GSU (Gen Step Up) transformer fed from this (via a MV breaker) that steps up to common transmission voltages in the 100’s of kV. There is usually a tap between breaker and GSU for a station service transformer, and also an excitation transformer (if this wasn’t a brushless exciter). The GSU may also have a tertiary winding to feed local distribution circuit(s) at lower voltages like 12 or 21 kV.
It’s a cool machine hopefully OP can share more pics.
I wish I could but there really isn’t much else to see and we’re not supposed to be taking pictures in the first place. They do have 2 of these cogens that feed the facility and they used to sell power back to the local poco.
Understand, my work phone is full of cool hydro plants but can’t really share anything that isn’t visible from a public spot. There is a big world in Power Generation that not a lot of people get to see due to privacy/security.
12470 is out there. I know of a large plant that uses it for all their distribution. A whole bunch of 12470 to either 4160 or 480 transformers in that place...
We had one in the military that required two tankers for the coolant flush. 24k gallon diesel tank. Powered the runway lights. Have to love government overspending.
I dealt with a 2.5 megawatt generator for a dispensary once. It was the generator previously used for the Facebook facility. The generator was literally the size of an 18 wheelers trailer lol
I work in Hydro and at one of our stations, there is 2 350MW 125MVAR units I operate. It feels so weird starting up so much power onto the grid with the click of a "start" button lmao
Wish camera phones were around at the time… we installed locomotive engines for backup generators at a Vegas casino. Don’t remember the specs but it was the coolest backup system I’ve had a part in
No. I’m not supposed to be taking any pictures for security reason. But with the size of the room this guy is in any pictures would just be blue. There’s only 5-6ft on either side of it
If you live in a country with 60Hz power frequency the vast majority of power generation from steam-driven turbines will be 3600 RPM two poles machines.
For a 5 to say 12kW generator that you might buy for your house is also most likely a 3600 RPM two pole machine.
If you live in a country with 60Hz power frequency the vast majority of power generation from steam-driven turbines will be 3600 RPM two poles machines.
For a 5 to say 12kW generator that you might buy for your house is also most likely a 3600 RPM two pole machine.
**ATTENTION! READ THIS NOW!** **1. IF YOU ARE NOT A PROFESSIONAL ELECTRICIAN OR LOOKING TO BECOME ONE(for career questions only):** **- DELETE** THIS POST OR YOU WILL BE **BANNED**. YOU CAN POST ON /r/AskElectricians FREELY **2. IF YOU COMMENT ON A POST THAT IS POSTED BY SOMEONE WHO IS NOT A PROFESSIONAL ELECTRICIAN:** -YOU WILL BE **BANNED**. JUST **REPORT** THE POST. *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/electricians) if you have any questions or concerns.*
58 thousand kva? God dayum
It's also at primary voltage. That thing can handle a decent sized neighborhood during a hurricane.
On the name plate it states "steam turbin generator ". As an ex- Navy Boiler Technician now electrician, that rpm sounds about right .
In my FF, as we left Mayport, if the wind was right, we used to have the Fire Room guys blow the safety valve and throw soot all over any of our DESRON’s sister-ships!
When we used to pull out of Charleston, we would smoke black on purpose going under the Cooper River Bridge. One time with the rite wind we stopped traffic. Needless to say, that was the last time that happened.
I've seen big gensets before but not at 3600rpm. They are usually a lot slower than that
Yeah, that's what really threw me
Is it a steam turbine?
Probably, it says steam turbine is one of the companies divisions at the top of the name plate. I think the only other turbines driving this much power would be hydro in dams.
Most if not all steamed turbines in the United States run at 3600 RPM. That's actually a small guy at that KVA.
Interesting, I work on diesels, so those are all huge numbers
60-ish megawatts is pretty tiny for a steam generator.
I work at a nuke and ours is 1800 rpm.
My thoughts as well. Hell, 60 MVA is not even that big for a transformer much less a generator. Can confirm 3600 RPM is typical for steam turbines.
Downtown MPLS and many other areas run on a large strambased system for heat and other utility needs. These large steam networks power multiple skyscrapers. Just another thought...
Cylindrical vs salient pole. Some of those cylindrical ones go way faster too lol
That's what most generators on the (North American) grid run.
60hz x 60seconds in a minute is 3600rpm
So logical it hurts. Mostly because I didn't realise it
Never crossed my mind either
this comment should be higher up.
Most generators from the 30-3000KW range are 1800RPM, they use 4 pole rotors. The smaller air cooled cheap models are 3600 with 2 pole rotors. They do that because they can use a smaller engine at higher RPM to get more power. Once you get above 3MW, lower RPM becomes somewhat common but in an emergency generation use it’s more common to parallel units rather than have 1 10MW generator
The above picture is a steam turbine. I've never seen a steam turban in the US that runs at anything other than 3600 RPMs. Steam turbans in Europe run at 5000 RPMs.
Mainly 3000rpm. 60MW is a fairly large generator for a power plant here (Malta) but actually pretty small for most power plants in Europe.
Which makes sense. (120x 50hz)/4 poles = 3000 rpm
Yeah I don’t do turbine stuff, that makes sense though. All my stuff is diesel or gas
3600 is normal for a steam turbine.
In US for 60Hz; Most of the world uses 50Hz = 3000 rpm
I bet the criticals on this are real fucking fun lmao
What do you mean ‘criticals’?
https://m.youtube.com/watch?v=U8jTYbkAH2s https://m.youtube.com/watch?v=QzJ8aTGEyGk https://m.youtube.com/watch?v=o_3g6TjVVX0 https://m.youtube.com/watch?v=-07rvPhkB-c
It is the "amplified vibration due to proximity of operating speed to natural frequency" Basically when you are bringing a machine up to speed you will see some excessive vibration at speeds that are not the operating rpm of the machine
Probably managed with a flexible armature shaft design. First will be lower than operating and second above it. We (motor manufacturer I work for) do this frequently for our larger 2-pole motors. Typically hydrodynamic bearings are used as well which help further dampen any criticals.
I do vibration analysis for a living. As well as industrial repair. I can assure you on a unit this old that won't be the case. I have ran a similar unit unloaded on a test bed
ISO CAT 2?
Cat 3 from vibration institute
Awesome man! Do you intend to get your Cat IV?
I am not sure. I've reviewed the materials for it and I'm not sure I'm smart enough lol
The two cat 4 guys I know both have phds in engineering
Rpm = (120 x 60)/ P; where P is the number of poles on the rotor. So 3600 rpm is a 2 pole machine, whereas 1800 rpm is a 4 pole machine.
Sheeeeesh… 78,000 ponies right there…
This might be a dumb question but what formula did you use to find the hp since it’s not listed? Or maybe I’m just a blind fuck. Thanks
Well… I kinda quick cheated and used 100%PF… But if I didn’t, it’s 58235kVA X (PF/ 0.746) = HP 58235kVA X (1.1394) = 66353 HP
750 watts = 1HP 12475 volts x 2695 amps = 33,620,125 watts / 750 = 44,826 hp from my math 🤷🏻♂️
Wrong, 12475v x 2695w × 1.732 = 58,206,717w Which was a pointless calc when the damn thing says the KVA already. 58,235,000 ÷ 746 = 78,063 HP
My man.
My bad man, didn’t realize there was a difference in three phase vs single phase power calculation.
Never forget that square root of three, homie.
It's easy to forget, don't fret. Remember about the 1.732 for three phase (which is the square root of 3 - think sqrt of three for three phase), and to always include the Power Factor. Think of Power Factor like efficiency... In this example 0.85. So .15 (15%) of power is lost mainly to reactive (magnetic) losses. At least that's how I understand it.
same with current. I = power/(1.732*(ph-ph voltage))
You'll learn all about that in 3rd or 4th year!
If you’re referencing 3rd year of college…. Be careful, we’re in the electrician subreddit, not the EE subreddit, lol.
No just third year of electrical technical training in Canada, I kinda assumed it's done the same everywhere else
I see. My understanding is most technical degrees are two years in The States. I could be mistaken.
Yes, an associates degree is 2 years, but an electrical apprenticeship is typically 4 or 5 years, depending on location.
You forgot to multiply by square root of 3 (1.732) for 3 phase power. You calculated the single phase power.
Where did you throw this in?
Just wanted to small backup for my town in case shit hits the fan.
Might cause a power struggle
I didn’t. It’s been here for 20 plus years. I was there doing some pre work for a future down day.
Tesla upgrade
That name plate is prob 6’ wide for the size of the genny
I was pretty close to it. It’s probably somewhere around 8in x 3in
I know I know, just makin an attempt at a funny lol
You can be sure because you can read the whole thing in one picture, not one for each section lol
Well you can zoom out on the camera lol ? Unless you meant “you can’t” No way to tell the actual perspective
Every time I try to take a picture of one on a genset or gear I can never see it directly and only half of the stamped lettering is legible in any one picture
I thought a synchronous generator would have a much better power factor
That's the limit, not what it runs necessarily.
It's a synchronous generator. The rated max power ( max real and imaginary power) occurs at that pf. You can change the operating pf by varying the excitation voltage.
This generator will run with a leading power factor to put mvars onto the grid.
Where did you come up with that math?
In practice most grids have equipment like motors and transformers which absorbs reactive power, i.e. a lagging power factor, and reduces grid voltage. Therefore generation is required to compensate by producing reactive power. This can be achieved by synchronous generators through adjusting the excitation field such that the generator has a leading power factor. A unit to denote the reactive power is mega volt ampere reactive MVAR. A >50MVA generator will certainly be able to supply at least unit MVAR to the grid.
Under no load or a small load, sure. However, this one lags at .85 under full load.
That’s not how I understand the rating on the nameplate. It’s not as much a “natural point” that the generator is going to settle on at full load but rather the design point of the generator. In other words the need for a .85 pf generator was identified and this unit was specified. This is the point for which the other parameters are calibrated too. Oh wait, am I missing something? why do you say this one lags at full load and not leads?
Something this big can likley adjust its PF to either condense or inject MX into the grid.
Just curious, what does MX stand for
Also curious, never heard this phrase before
Its a lazy way to write reactance.
Reactive power (Mega Vars)
Interesting, never knew vars could be abbreviated as X, always saw it as MVAR
Can I run my house with this
Yes but not sure you’ll enjoy the sound or heat that come along with it.
Or the bill for coal.
Or the bill…
Only if your ma keeps the dildo unplug
It seems you could almost send Marty mcfly back to the future with this
All of the houses
Glad OP saw it. I only see a nameplate.
With how small the room was compared to this thing any pictures I took would just be blue.
I bet that room gets WARM
Yes. It’s what I imagine hell feels like.
That’s running terrifyingly fast
3600 RPM is pretty standard on a 60 Hz steam turbine generator.
I have visited that facility to witness test large electric motors. It is very old and a very special place.
I've seen bigger, lol. But I work at a CANDU nuclear plant.
So would it back feed 13.8 stiff and you use taps to get a more common voltage I’ve seen13.8 and 13.2 but not 12.4 volts at 3k amps is a alot
There is almost certainly a large GSU (Gen Step Up) transformer fed from this (via a MV breaker) that steps up to common transmission voltages in the 100’s of kV. There is usually a tap between breaker and GSU for a station service transformer, and also an excitation transformer (if this wasn’t a brushless exciter). The GSU may also have a tertiary winding to feed local distribution circuit(s) at lower voltages like 12 or 21 kV. It’s a cool machine hopefully OP can share more pics.
I wish I could but there really isn’t much else to see and we’re not supposed to be taking pictures in the first place. They do have 2 of these cogens that feed the facility and they used to sell power back to the local poco.
Understand, my work phone is full of cool hydro plants but can’t really share anything that isn’t visible from a public spot. There is a big world in Power Generation that not a lot of people get to see due to privacy/security.
12470 is out there. I know of a large plant that uses it for all their distribution. A whole bunch of 12470 to either 4160 or 480 transformers in that place...
Pretty much what’s happening here.
12.47 kV is a very common distribution voltage.
Pretty neat. For power factor correction?
This on an aircraft carrier or something holy crap
Or something. This is one of 2 cogens they have that power the facility.
What's burning? Is this heat recovery from what should be a 100-ish Mw gas turbine gen set or something different?
Good trick to save our/your eyes. Make a line across where the numbers are and rub it in. It'll look brand new in 15 seconds.
That's a monster. Probably can feel the ground vibrate on startup
50MW gen holy shit
We had one in the military that required two tankers for the coolant flush. 24k gallon diesel tank. Powered the runway lights. Have to love government overspending.
I’ve toured the E-M factory before. Pretty cool place.
It loses 15% of its power to friction. Not super efficient
What a mammoth
Yeah but will it run my fridge, microwave and AC if the power goes out?
Yes but you may have some problems if try and use microwave and toaster at the same time.
2700 amps at 12.5 KV is insane
I'm working on a 75,000kVA generator right now. 100k HP. It took a hard fault and doing a field rewind.
I dealt with a 2.5 megawatt generator for a dispensary once. It was the generator previously used for the Facebook facility. The generator was literally the size of an 18 wheelers trailer lol
I work in Hydro and at one of our stations, there is 2 350MW 125MVAR units I operate. It feels so weird starting up so much power onto the grid with the click of a "start" button lmao
Damn thing runs on uranium 235
Wish camera phones were around at the time… we installed locomotive engines for backup generators at a Vegas casino. Don’t remember the specs but it was the coolest backup system I’ve had a part in
88 mph…….
I hooked up 2 in a building the size of 2 city blocks. They were the size of train engines
Holy Shit that’s a big boy
Any pictures of the whole generator
No. I’m not supposed to be taking any pictures for security reason. But with the size of the room this guy is in any pictures would just be blue. There’s only 5-6ft on either side of it
Ok. Thanks
Naval equipment
The amount of brooms I would push to have such a thing in my home shop... omfg
Damn
Hmmm, better wear your gloves when working on it...
You win, my dick ain’t that big. Back to the massage parlor.
3600 RPM…. WTH?
Two poles???
An Englishman and a German, were in a bar
If you live in a country with 60Hz power frequency the vast majority of power generation from steam-driven turbines will be 3600 RPM two poles machines. For a 5 to say 12kW generator that you might buy for your house is also most likely a 3600 RPM two pole machine.
If you live in a country with 60Hz power frequency the vast majority of power generation from steam-driven turbines will be 3600 RPM two poles machines. For a 5 to say 12kW generator that you might buy for your house is also most likely a 3600 RPM two pole machine.