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Capacitor Help

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Clinton

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Hello,

I have two cermic capacitors which I need help in telling what they are. The markings on the caps are;

1) 104M 9419

2) 471 JCP416


Thanks

Clinton
 
the 104m capacitor means it's 0.1uF cap
the 471 it 0.47nF
use the formula:
first and second numbers* 10^third number*10^-12=capacitance
 
SupeR-NovA said:
the 104m capacitor means it's 0.1uF cap
the 471 it 0.47nF
use the formula:
first and second numbers* 10^third number*10^-12=capacitance

That seems rather complicted :?

Just think of the last digit as the number of zero's at the end, with the result in pico-farads:

So, 471 is 47 and one 0 = 470pF

and 104 is 10 and four 0's = 100,000pF, 100nF, or 0.1uF.
 
Check out this Capacitor Tutorial Article, which explains most of what capacitors are all about. I end up referring back to this page every time I build something.
**broken link removed**
 
ceramic caps

:D hi everybody,

here's an article send to me and maybe some of you have also received this. this concerns about ceramic caps causing overvoltage. am attaching the doc. here :D
 

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  • application_notes.zip
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SupeR-NovA said:
the 104m capacitor means it's 0.1uF cap
the 471 it 0.47nF
use the formula:
first and second numbers* 10^third number*10^-12=capacitance
theres one problem with this formula if you do the cap that you claim is .1uf it comes out to be .00001 which is 10uF not .1uF and the .47nF cap will come out as 47nF or .000000047. So either you screwed up on the formula or you just aren't that smart no offense but giving bad information isn't a good thing since it could be the difference between a bad accident and a good circuit.
 
Painandsuffering said:
SupeR-NovA said:
the 104m capacitor means it's 0.1uF cap
the 471 it 0.47nF
use the formula:
first and second numbers* 10^third number*10^-12=capacitance
theres one problem with this formula if you do the cap that you claim is .1uf it comes out to be .00001 which is 10uF not .1uF and the .47nF cap will come out as 47nF or .000000047. So either you screwed up on the formula or you just aren't that smart no offense but giving bad information isn't a good thing since it could be the difference between a bad accident and a good circuit.
Pain, the equation is correct. Example one:

104 = 10*(10^4)*(10^-12 )= 10^-7 = 0.1uF

Example 2:

471 = 47 *(10^1) * (10^-12) = 47*10^-11 = 470pF
 
Capacitor tolerance codes

As mentioned, that letter following the value (e.g., the "M" in "104M") is the tolerance of the cap. Since I have it handily stored here on the HDD, I'll just pop it onto this post for all to have handy. This list isn't found just anywhere and there are a few recently-added letters that I found that I hadn't known about. The non-symmetrical tolerances, e.g., +80/-20%, are used on "bulk" capacitors, those caps that are used for power supply filters and decoupling, where you want capactance, the more the merrier, but don't want it below a certain value. Here's the codes:

B = ±0.1pF
C = ± 0.25pF
D = ±0.5pF
E = ±0.25%
F = ±1.0pF
G = ±2%
H = ±2.5%
J = ±5%
K = ±10%
L = ±15%
M = ±20%
N = ±30%
P = -0, +100%
S = -20, +50%
W = -0, +200%
X = -20, +40%
Z = -20, +80%

Dean
 
Capacitor Information

Excellent information all. I particularly like the tutorial page.

One thing I'm still wondering about is the voltage rating. Take the 104M for example. It's a ceramic disk capacitor. Is there a way to determine the voltage rating ? Does the color of the cap help ?

Thanks
Marc
 
Ron H said:
Painandsuffering said:
SupeR-NovA said:
the 104m capacitor means it's 0.1uF cap
the 471 it 0.47nF
use the formula:
first and second numbers* 10^third number*10^-12=capacitance
theres one problem with this formula if you do the cap that you claim is .1uf it comes out to be .00001 which is 10uF not .1uF and the .47nF cap will come out as 47nF or .000000047. So either you screwed up on the formula or you just aren't that smart no offense but giving bad information isn't a good thing since it could be the difference between a bad accident and a good circuit.
Pain, the equation is correct. Example one:

104 = 10*(10^4)*(10^-12 )= 10^-7 = 0.1uF

Example 2:

471 = 47 *(10^1) * (10^-12) = 47*10^-11 = 470pF
Sorry to say this man but if the equation isn't wrong then your answer is take your calculater and find your answers then switch it to engineering notation. You'll come up with 10uf and 47nf.
 
equation

ok 10*10^4=1,000,000 or 1M. Then you multiply this by 10^-12 and you get .00001 which is 10uF....!!! This is what my graphing calculator gets and what the scientific calculator on the computer gets and what about 3 other people here with me are getting so Your numbers are wrong man. Just trying to help the guy out so he doesn't mess up what he's trying to build with the caps.
 
One thing I'm still wondering about is the voltage rating. Take the 104M for example. It's a ceramic disk capacitor. Is there a way to determine the voltage rating ? Does the color of the cap help ?

That's a good question. I've often wondered that myself, especially for ceramic caps. I go by a general rule of thumb: If I don't know that max volts a cap can handle, I usually assume it is 9 volts and I wont use it for anything over 9 volts. Granted, a lot of ceramic caps are rated greater than 9 volts, (I think most are 15 volts and up). Of course, this rule of thumb goes out the window when the capacitor is very small for the amount of capacitance. For instance, 100,000 pF (104) ceramic disc capacitors are generally around 1/4" in diameter. So if I find a 100,000 pF ceramic disc capacitor that is smaller, I generally assume that the voltage rating has decreased since the size has decreased.

To be proper, and safe: Ideally, if the voltage rating is unknown and cannot be discovered, the capacitor shouldn't be used in a circuit. Since ceramic caps are very cheap, I would go ahead and purchase a cap where the voltage rating is known.

Most other capacitors will have a voltage rating stamp on the capacitor itself. You see this ALWAYS with electrolytic and tantalum caps. Most of the time, polyester and other specialty caps will have voltage rating indicated on the cap as well.
 
Capacitors and Voltage ratings

Thanks, I guess I should have avoided the "big box 'o caps" at Radio Shack !

I'll go "shields up" if I use one in a circuit. I'm just starting out so will be mainly using 6V-12V. Anything over 9 and I'll make sure it has a stamp.

Thanks
Marc
 
Thanks, I guess I should have avoided the "big box 'o caps" at Radio Shack !

I'll go "shields up" if I use one in a circuit. I'm just starting out so will be mainly using 6V-12V. Anything over 9 and I'll make sure it has a stamp.

You should be okay using the big box o caps (You stated well if I may say so. :D ) with your 9-12 volt circuits. I don't think radio shack would sell caps that are rated under 15 volts. The radioshack website offers specifications on most of their products. This specification (IF there is one for the box o caps) should state what the voltage values are. Nevermind, I just checked, they don't have specs for their box o caps.

Maybe the box o caps container has the voltage values listed?
 
Re: equation

Painandsuffering said:
ok 10*10^4=1,000,000 or 1M. Then you multiply this by 10^-12 and you get .00001 which is 10uF....!!! This is what my graphing calculator gets and what the scientific calculator on the computer gets and what about 3 other people here with me are getting so Your numbers are wrong man. Just trying to help the guy out so he doesn't mess up what he's trying to build with the caps.

(1) 10 * 10^4 = 10^5 = 100,000... not 1M
(2) 1M * 10^-12 = .000001... not .00001

Pain, you don't need a calculator to figure this out, and you obviously don't know how to use your calculators. You need to take a basic course in exponential notation so you can do a sanity check on your results. You can multiply by simply adding exponents, like this:

10^x * 10^y * 10^z = 10^(x+y+z)

so

10 * 10^4 * 10^-12 = 10^1 * 10^4 * 10^-12 = 10^-7 =0.1uF
 
Capacitor Information

Maybe the box o caps container has the voltage values listed?
No such luck. Some of the capacitors have stamps (those large enough to fit the printing). Most just have the capacitance codes.
 
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