California Electricity Dilemma

[potatochips]

Also, there is nothing wrong with decay heat, or the thermal mass of a reactor in normal start up or shut down- on the contrary you want a gradual heating in a reactor. These are all taken into account and dealt with accordingly by the operators.

I said this in an earlier reply. Thanks for using it to prove my point because a nuclear unit takes days to start up versus hours for coal. Days because the system is significantly more complex because it has significantly more parts than coal.

Refueling isn't an issue either when it is done in intervals spanning years. A coal plant needs to be refueled continuously, in real time.

A coal fired plant does not need to be slowed or shut down for refueling. A nuke plant does. This downtime is time not generating revenue.  Refueling operations are big big jobs for reactors.

 

[labboy]

We have had solar for 10 years now and have an all electric car as well as a plug-in hybrid. We have done what we can to conserve and make good choices for vehicles, appliances, solar, etc. However, this requirement is going to be a big burden for us as well as many of our neighbors. Our house was built in 1929 so this is going to necessitate major electrical work and upgrading our electrical panel. While we can afford it, I worry about some of our neighbors. They need to have some provision to provide assistance to people who need to
do electrical modifications to comply with the new requirements.

Bob

 

[Chetlaham]

"hahaha what are you talking about?"

These terms can be Googled.

"No, they're not, and I dont think you know what that means."

You're telling my 3 mile Island was controlled by servers and desktop computers?

"So if I go from two pumps to eight, that's not more complex?"

Depends on how those pumps are controlled. If the two pumps are lead/lag, VFD driven, and controlled by PLCs monitoring many variables vs 8 pumps switched on across the line by an operator the 8 pump approach would be simpler.

"I dont even know what you're trying to say here."-- Nuclear plants on an elementary level are designed to trip rather easily when something goes wrong.

"Certain rad detectors have the ability to trip the facility. Supplementary or not, these things increase the complexity of the overall facility."-- Not much more complexity.

"I don't think you understand controls in an industrial setting."-- So your saying every single data input automatically controls, or has the ability to trip the reactor instead of just lighting up an annunciator?

So in your words, how does France keep the lights on? I've never set foot in RTE or a French generating station, so you would easily know more than me on this one.

"What the hell is a AC and DC control schematic? I've never heard of that before."

If you don't know that generating station and substations have an extensive 125 volt DC system to control indicators, sensors, breaker trip solenoids, gauges, auxiliary relays, protection relays, ect ect then your rebuttal would be mere projection.

AC power can dip and sag during a fault, so you have to use batteries and DC power for the sensing and control in any plant.

 

[potatochips]

These terms can be Googled.

I did, only two exist. And theyre terms used in accounting.

You're telling my 3 mile Island was controlled by servers and desktop computers?

The controls for second generation and third gen reactors is mostly based off of PID loops backed by pneumatics. There is discreet controls, which is what you call "relay logic", cannot do anything but yes/no controls. Thats where pneumatics and PID loops come in to play, for controls requiring setpoints and ranges. Which you need very very much in a power plant. Power plants cannot be controlled purely by discreet, binary, yes/no controls. You need controls that can vary 0-100 and everywhere in between and this is essence of pneumatics and PID. 

Depends on how those pumps are controlled. If the two pumps are lead/lag, VFD driven, and controlled by PLCs monitoring many variables vs 8 pumps switched on across the line by an operator the 8 pump approach would be simpler.

 

Okay, well, maybe I need to be more exact here. If a process requires eight pumps to function, where as another process that produces the same results requires two... The one with eight is more complex. Also, no one says "swtiched on across the line". Thats not what "Across the line" means. No one says that. 

Nuclear plants on an elementary level are designed to trip rather easily when something goes wrong.

 

Every industrial plant/process is designed to easily trip. Thats what an SIS loop is. 

Not much more complexity. 

 

So a whole department thats tasked with maintaining, tracking, issuing, observing, etc this whole silo which probably employs people in the double digits is "not much more complexity"?

So your saying every single data input automatically controls, or has the ability to trip the reactor instead of just lighting up an annunciator?

 

I didn't say that. You said half the instrumentation doesn't do anything other than display data. Thats an awful lot of instrumentation thats on an advisory role only... I've never seen a plant like that before. 

So in your words, how does France keep the lights on? I've never set foot in RTE or a French generating station, so you would easily know more than me on this one.

 

I do. When a plant is synced to the grid and generating power, there is minimal operator intervention. Any plant that requires extensive operator intervention for steady state is a shitty plant thats dangerous and unstable, no one would design a plant to be like that. Load demands are a normal operating cadence. Operators would not intervene, automatic would take care of that. Just so happens that thermal plants figure it out quick. Nuclear takes a long time for a load change to smooth out. Chances are, at those times, a distribution centre would load shift before hand to enable a reactor to handle a load change. 

If you don't know that generating station and substations have an extensive 125 volt DC system to control indicators, sensors, breaker trip solenoids, gauges, auxiliary relays, protection relays, ect ect then your rebuttal would be mere projection.

 

I knew what you were saying, but I was rebutting that way because thats not at all what its called in industry to prove that you have no idea what you're talking about. Just like how 125V DC systems for controls are not a thing either, its 24V at  4-20mA. What you were referring to is the instrumentation or controls system. But what you don't realize is that there are a shit load of AC and DC busses in a power plant. DC exciter system for the generator. AVR for the generator. AC back up bus. AC Station Power. DC back up bus. DC UPS bus. If you're going to pretend you're knowledgeable in industrial processes, at least talk the talk and use industry terms. 

AC power can dip and sag during a fault, so you have to use batteries and DC power for the sensing and control in any plant.

 

Thats not why DC is used for controls. 

 

Also, what you uploaded was a grainy single line diagram. SLDs is what theyre called in industry, not schematics. Again, i<span style="font-size: 12pt;">f you're going to pretend you're knowledgeable in industrial processes, at least talk the talk and use industry terms. </span>

[this post was last edited: 11/26/2022-17:35]

 

[Chetlaham]

Your rebuttal tells me you aren't someone wanting to have a genuine debate, rather just wanting to pitch an ad hominem "gotcha!"

I felt schematic was more fitting in a form with limited electrical engineers, but it doesn't matter since I would have been darned the other way too.

I am far more aware than you can comprehend of each voltage level and power system in a generating station. I know what a GSU is, a station service transformer, a unit aux transformer, 6.9Kv buses, associated step down transformers to 480 volts, MCCs, 480 volt emergency bus, high resistance grounding (where present) along with everything else I wont bother listing. Along with how to calculate the sequence components to obtain available fault current, BIL, 50/51/67 relay settings, ect.

You can download the full size here:

 

[potatochips]

I am far more aware than you can comprehend of each voltage level and power system in a generating station.

Well thats good, considering the other year you told me in order to generate more power all you have to do is spin the generator faster.

 

[Chetlaham]

My Bad- I goofed

Go to the three dots, you can click download:





These are just two 125 volt DC panel-board single line diagrams I posted to show the existence of 125 volt DC (in a power station) powering things like the steam dump valve controls, 138kV & 345kV relaying, reactor protection (see red arrows).

 

[Chetlaham]

"Well thats good, considering the other year you told me in order to generate more power all you have to do is spin the generator faster."

Post the reply, otherwise I never said it.

I was either:

a) referring to a DC PM generator

b) saying that 60Hz power systems require less iron than 50Hz systems for the same MW transmitted.

 

[Chetlaham]

"Thats not why DC is used for controls" 

I just want to address this reply, even though I shouldn't.

Voltage sagging during a fault is exactly one reason why DC is used. A 3 phase bolted fault on a 345kV line in front of the station drops the voltage on the substation bus to essentially zero. This would cause the SEL relays to simply black out being incapable of processing CT and VT inputs to exports a trip command out to the breaker(s) and even if they could, the voltage would not be high enough to pull in the trip solenoid(s) and as such the fault would remain until remote 21 elements picked it up- assuming said remote relays have enough voltage or batteries and a DC bus in their station.

Same goes for the reactor controls, they must receive uninterrupted power. Hence why in the diagram with the red arrows 125 volts DC is converted to 120 volts AC instead of being taken directly from the 208Y/120volt panelboards throughout the station.

That is exactly the reason, at least one of them.

 

[potatochips]

Your rebuttal tells me you aren't someone wanting to have a genuine debate, rather just wanting to pitch an ad hominem "gotcha!"

What you posted was a wiring diagram for a 125V DC switchgear control, not for an instrumentation controls system which you said earlier was powered by 125V DC. Were talking about plant controls and instrumentation. Not distribution controls and instrumentation. You're bending the argument because I caught you in a trap.

 

[potatochips]

Reply #25 and #27. https://www.automaticwasher.org/cgi-bin/TD/TD-VIEWTHREAD.cgi?78407

I have to stop arguing with you because it's insane how someone can continually double down on their own stupidity and continually prove themselves wrong. All you do is throw big words around to look like your versed in power plants and controls when really you have absolutely zero clue. Its painfully obvious youre not educated in this field and you don't work in it. Stop pretending.

 

[Chetlaham]

Have a read of the circuit designations...

 

[Chetlaham]

You mean this?

"@potatochips: Doesn't excitation regulate reactive power (MVAR) output while speed is in proportion to real power (MW) output?"

Yahhh, if you try and accelerate a synchronized turbine, torque will go up and the generator will output more MWs.

It might not actually speed up (minus the very insignificant increase in grid frequency) up but sure does pickup more watts.

 

[Chetlaham]

Not bending- plant controls are indeed (at least the plants I've seen) fed from the 125 volt DC system. Even some of the ones taking in AC, get power via an inverter fed by the 125 volt DC bus.

 

[potatochips]

You havent been in a single plant. You don't know what you're talking about. HART, Profibus, Foundation Fieldbus are modern comms protocols that range between 1-32V DC. Christ, even Bailey Infi 90 from the late 80s is a 24V DC protocol. Infi 90 is probably the last DCS certified for nuke plants in North America. You seriously need to stop doubling down on your ignorance. You don't know what you're talking about. Even other users on this forum, even in this very thread, posted to point out that you're mostly full of shit. So, I am done discussing with you.

 

[Chetlaham]

Thats not what "Across the line" means. No one says

Actually, everyone is saying that because it is the correct term, as used in the electrical trade:

https://www.google.com/search?q=acr...oBBggBEAEYCdoBBggCEAEYCA&sclient=gws-wiz-serp

https://worldwideelectric.com/product-category/motor_controls/across_the_line_motor_starters/

Chances are if a motor is not run by a VFD, it will be controlled by an across the line motor starter.

I know this forum, and the world in general is deeply anti nuclear. Attacking the credibility of messengers has become the standard modus operandi across the internet in 2020 onward, however it doesn't change the facts or where the future will lead us.

 

[Chetlaham]

I am not denying the existence of any of those communications protocols, their use in power plants or their voltage signal range. I never did. As much as Im not denying IEC-61850 in substations.

My only point was that certain equipment, protection and control devices are supplied at 125 volts DC.

Thats it!

You then stretched that to say I had insinuated 4-20mA current loops were running on full 125 volt DC power.

 

[Chetlaham]

Others saying I'm full of it

Oh, I know LOL! There are a select few members on here who chronically disparage anyone with an opinion, experience, preference, knowledge or outcome that happens to differ from theirs while using their service tech career as justification.

I'm not the only target. Dozens of others are, in particular those who collect vintage appliances. They constantly have to prove there is something fundamentally wrong about restoring or using a dated machine.

Their hubris catapulting personal attacks isn't unique by any means and its exactly the polarizing force driving humanity apart today. So be it.

 

[sudsmaster]

OMG, what did I start with this thread?

 

I am reminded of a certain classic request from about 30 years ago...

 

 

[neptunebob]

It's time for more Fiber!

These 2 surly engineers are just like the ones in my neighborhood growing up. Time for the Metamucil 2 Week Challenge!  What will be your Metamucil story?

 

By the way, it is any coincidence that most of those surly engineers worked for Westinghouse?

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