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If the positive plate on a charged capacitor will pass current to the negative...

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Nevertamed
#55
Dec16-12, 12:42 PM
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Quote Quote by Ratch View Post
Nevertamed,



Caps are not charged, they are energized.

Ratch
oh lord...
jim hardy
#56
Dec16-12, 12:58 PM
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But how does that apply to what we were discussing?
well, i interpreted several posts as spiralling around the meaning of "charge" vs "energize"

and if i missed where either was defined, it's my bad.

So i was trying to provoke a clarification .
Ratch
#57
Dec16-12, 01:58 PM
P: 315
jim hardy,

So i was trying to provoke a clarification .
A noble endeavor. Here are some examples.

1). This is an example of someone asking how to de-energize a capacitor safely.
http://answers.yahoo.com/question/in...=1006021608394

2). This is an article about energizing and de-energizing a load involving switching capacitors. They never say "charging". http://helios.acomp.usf.edu/~fehr/312ecm381.pdf

3). Another article about energizing capacitors, where they mention energizing capacitors 8 times. See the title of Fig. 3. http://www.southernstatesllc.com/***...pdf?1274707457

4). An article about power factor capacitors. See the fourth paragraph which says, "When the motor is energized, the capacitor is energized. When the motor is de-energized, the capacitor is de-energized." Their words, not mine. http://myronzucker.com/Resources/Capacitalk100.html

5). Wanna learn how to energize and de-energize a electric energy storage device? Read on. http://www.freepatentsonline.com/7157884.html

6). Get taught by a lady, no less, on how to energize a capacitor. http://www.soyouwanna.com/run-capacitor-31920.html

7). These folks will test your capacitor before you energize it. Their words, not mine. http://www.hdelectriccompany.com/hd-...uick-Check.htm

8). Look at the second sentence from the end of the abstract. http://www.atpower.se/Papers/Ananlys...e%20system.pdf


Nevertamed,
oh lord...
Is that a plea for help, or an acknowledgement that you are in over your head?

Ratch
sophiecentaur
#58
Dec16-12, 03:31 PM
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I looked at those links. Most but not all of them worked. I am now a bit more convinced about how commonly the term 'energise' is used in certain restricted circumstances - practical ones when a capacitor is, in fact, used to store energy explicitly. I needn't bother with a google search with 'charged capacitor' we know there would be a deluge of both peer reviewed academic papers, practical applications (and text books). I will still stick to charging capacitors until I need to 'store energy'.
jim hardy
#59
Dec16-12, 06:53 PM
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Fair enough.

Perhaps the understanding gap comes down to local dialect.

I grew up in an industrial power environment. We "Energize" equipment to make it run, ie connect it to its power mains.

A capacitor in that AC transients paper is 'energized' when in use because it's connected to its mains. "Charged" would be the wrong term because it's charged, discharged, and recharged opposite polarity with every line cycle.

HD Electric company tester checks utility size capacitors before connecting them to the powerlines ; a good idea because powerline level faults are quite pyrotechnic. They didnt say how it works.

Sorry, but Esmeralda doesn't sound very credible.

MyronZucker clearly shows connection to mains as 'energizing' his capacitor bank.
USF.edu seems also to use 'energize' in the same sense; and he has a nice bit on why switch contact design is such an art - transient current and arcing .

Okay, all that said:

In my background, to "Charge" a capacitor implies to connect it to a source of DC and allow charge(Coulombs) to accumulate per Q = C*V . I do that sometimes just to see if it holds charge, ie checking its insulation resistance.
The energy stored is 1/2 C*V^2 and sometimes i'll short its leads and estimate from size of the spark whether its capacity seems intact. An analog meter is real handy for that test, observe how fast the cap discharges.

So given my background i was a mite puzzled by what appeared to be use of the terms interchangeably.

A cap that is charged has energy stored in its dielectric, but i was taught to call it charged. because it may not be connected to a power source anymore. Be careful when picking up capacitors......
One that's "energized" is definitely connected to a power source.

"Toto, I may not be in Kansas anymore."



old jim
Ratch
#60
Dec16-12, 06:58 PM
P: 315
sophiecentaur,

I looked at those links. Most but not all of them worked. I am now a bit more convinced about how commonly the term 'energise' is used in certain restricted circumstances - practical ones when a capacitor is, in fact, used to store energy explicitly. I needn't bother with a google search with 'charged capacitor' we know there would be a deluge of both peer reviewed academic papers, practical applications (and text books). I will still stick to charging capacitors until I need to 'store energy'.
As I said in post #51, a concensus does not determine the truth, but reason and facts do. Those of us in the know find it hard to describe a capacitor as "charged", when we know otherwise.

Ratch
Ratch
#61
Dec16-12, 07:08 PM
P: 315
jim hardy,

A capacitor in that AC transients paper is 'energized' when in use because it's connected to its mains. "Charged" would be the wrong term because it's charged, discharged, and recharged opposite polarity with every line cycle.
Any capacitor imbued with energy is energized, and has a voltage across its terminals. All capacitors have the same net charge, specifically zero.

Sorry, but Esmeralda doesn't sound very credible.
Why not?

In my background, to "Charge" a capacitor implies to connect it to a source of DC and allow charge(Coulombs) to accumulate per Q = C*V . I do that sometimes just to see if it holds charge, ie checking its insulation resistance.
The energy stored is 1/2 C*V^2 and sometimes i'll short its leads and estimate from size of the spark whether its capacity seems intact. An analog meter is real handy for that test, observe how fast the cap discharges.
That capacitor holds a voltage. Its net charge is the same before and after it is energtized and shorted.

So given my background i was a mite puzzled by what appeared to be use of the terms interchangeably.
Not by me.

A cap that is charged has energy stored in its dielectric, but i was taught to call it charged. because it may not be connected to a power source anymore. Be careful when picking up capacitors......
One that's "energized" is definitely connected to a power source.
Connected or not, any cap with a voltage across its terminals in energized.

Ratch
jim hardy
#62
Dec16-12, 09:53 PM
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I'll remember those things when travelling in your world.

Esmeralda seems clueless how a flash works.

Step 1

Energize the capacitor by making the connection between the battery and the flash capacitor. When you make the connection between the battery and capacitor, the capacitor will begin to absorb the electricity that is being released by the flash battery. Most capacitor run flash cameras have either a light that shows the capacitor is full or a soft tone that builds as the capacitor is being filled. When the tone stops, the capacitor is ready to release enough energy to operate the flash.
The connection is from the battery to the step up voltage converter, which energizes it. Upon energization, the stepup converter commences charging the capacitor to somewhere in the 350 volt range.
The "tone" is its stepup transformer raising the voltage .
Connecting the battery to the capacitor would charge it to battery voltage, ~1.5 volts.

But its okay, you explained your terms clearly. I can understand you now.

old jim
Nevertamed
#63
Dec16-12, 11:44 PM
P: 24
Quote Quote by Ratch View Post
jim hardy,





Nevertamed,


Is that a plea for help, or an acknowledgement that you are in over your head?

Ratch
i dont need help for your obstinacy, i think you do

P.S. please dont argue about the definition of obstinacy, i know what will happen afterwards


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