Electronic – Various Small capacitors’ markings

capacitormarkings

Wikipedia explains the basics about the markings of capacitors, here. It lacks many markings most of which confuses me:

Ceramic brown-yellowish cap

  • 104 K5K (small ) — what is the end "5K"? (Cannot be 5 kelvin as operating temperature!?)
  • 10 (box box, perpendicular right upermost corner) 35+ (Tantalum Cap, bigger variant of the last one
  • 154 C1K (what is C1K, some other notation to Wikipedia?)

Orange Ceramic

  • 333 K5X (what is 5X? X roman numeral?)

Brown Circle Slit

  • 10n (no other marking, what is the op.temp?) (Diameter: 7.5mm)
  • 27J 100V (what is 27J?) (Diameter: 4.9mm, blackdot on the head)

Blue Slit Square

  • (triangle) 104K X7R50 (What is triangle? X7R50? Operating V?) (side = 4.9mm)
  • 104 (side = 2.6mm, op.V? Tolerance?)

Questions about the bracketed

  1. How to know operating V without its explicit marking?
  2. What do the symbols, such as squares, plus-sign and triangle, mean?
  3. Can you evaluate the operating voltage from the size of the capacitor in the case when no marking or poor marking is given?

Best Answer

Generally there are two labels on most caps.

The first is the value, which is written:
<Digit><Digit><Exponential Notation>
It's generally in picofarads.

The second is the TempCo, or Temperature Coefficient. There are two common specification systems, namely EIA Class 1 and Class 2. This is the mysterious second label in most cases. It's generally written:
<Letter><Number><Letter> (though there are a few variations)
There are a few common tempcos - NP0/C0G, X7R, X5R, Y5V, Z5U

Tantalums, and bigger ceramics often also have the voltages:
<voltage number><+ or v>

Therefore:

  • 104 K5K (small )
    The value is 10e4, or 100,000 pf / 0.1 uF. The tempco is not standard, may be manufacturer specific/extended range.

  • 10 (box box, perpendicular right upermost corner) 35+ (Tantalum Cap, bigger variant of the last one)
    Need a picture to be more specific, it's very likely a 35v rated cap, from the 35+.

  • 154 C1K (what is C1K, some other notation to Wikipedia?)
    Capacitance is 15e4, or 150,000 pf / 0.15 uF. Looks to be a Class 1 dielectric from the C1K. Is this a large cap? the tempco is very good.

  • Orange Ceramic 333 K5X (what is 5X? X roman numeral?)
    33e3, or 33,000 pf / 33 nF. Tempco is either manufacturer specific, or incorrectly read.

  • Brown Circle Slit 10n (no other marking, what is the op.temp?) (Diameter: 7.5mm)
    10n very likely means 10 nf, or 10,000 pf. If it's ceramic, it's probably 50v. Likely a cheap part, if the voltage is not marked.

  • 27J 100V (what is 27J?) (Diameter: 4.9mm, blackdot on the head)
    Voltage rating is self evident. J is the multiplier, and I think there is a standard for letter multipliers, but I do not remember where to find it.

  • Blue Slit Square (triangle) 104K X7R50 (What is triangle? X7R50? Operating V?) (side = 4.9mm)
    10e4 is the value - 100,000 pf / 0.1uF Tempco is X7R. the 50 is likely the voltage rating.

  • 104 (side = 2.6mm, op.V? Tolerance?)
    10e4 - 100,000 pf / 0.1uF. Voltage is not known

This is kind of a guess. Anyways, it should show how this sort of thing works. Older parts may vary wildly, and it's always just a guideline. The best thing to do is find the cap's actual datasheet.

A lot of the parts have unusual tempcos. Is this a automotive/extreme duty part which contains these components?