Induction Heater Power Film Capacitors – Isolation, Day 6
A walk-through of different types of power capacitors that can be used in induction heater applications, ceramic, MICA, various types of film capacitors and extremely …
Tesla Coils, High Voltage and Electronics
A walk-through of different types of power capacitors that can be used in induction heater applications, ceramic, MICA, various types of film capacitors and extremely …
Published: November 5th 2009. Updated: December 27th 2020.
Metal foil and Polycarbonate dielectric film. See MKC for more details.
Metal foil and Polypropylene dielectric film. See MKP for more details.
Metalized Polycarbonate foil. Extremely temperature stable with less than 1% capacitance tolerance between -55ºC to +125ºC. Small size, high Q and capacitance stability make them ideally suited to filter network and other low-loss high frequency applications.
Metalized Polyphenylene sulphide foil. Extremely temperature stable with less than 1% capacitance tolerance between -55ºC to +125ºC. Small size, high Q and capacitance stability make them ideally suited to filter network and other low-loss high frequency applications.
Metallized Polypropylene foil. Known as power film capacitors. Very Low ESR, high stability and can found in 1% tolerance versions and can operate at temperatures up to 110°C. Suitable for high power AC circuits, circuits with high peak currents, high frequency resonant circuits, precision timing circuits, switch mode power supplies, sample and hold circuits, high frequency pulse discharge circuits and energy storage circuits. High internal resistance results in low levels of self discharge.
Metal foil and Polystyrene dielectric film. A metalized version was unsuccessful due to the low melting point of the dielectric. Suitable for precision-tuned circuits due to the extreme stability in the 0°C thru +50°C range and it has long-term stability. The dielectric has a maximum operating temperature of +85°C. It will melt at +100°C.
Metalized polyester foil. Known as Mylar, Polyester or Polyethylene terephthalate PET capacitors. Low ESR and can operate at temperatures up to 125°C, without much voltage derating. Suitable to be used for high frequency filtering, outdoor applications where moisture can be a problem, high voltage or current peaks in circuits and coupling and de-coupling circuits.
Looking at our capacitor we will see its marked 474J, this should be read as follows, 47 times the value that can be found in Table 1 corresponding to the 3rd number, in this case 10000. 47 * 10000 = 470000 pF = 470 nF = 0.47 uF with the J meaning a 5% tolerance. A second letter will be a temperature coefficient if its present. Judging by a capacitors size and type, you will quickly learn to determine if the value on the capacitor is given in pF, nF or uF.
If a capacitor is f.ex. marked 2A474J, the capacitance is decoded as described above, the two first signs is the voltage rating and can be decoded from table 2 here below. 2A is 100VDC rating according to the EIA standard.
Some capacitors are only marked 0.1 or 0.01, mostly in these cases the values are given in uF.
Some small capacitance capacitors can be marked with a R between numbers, f.ex. 3R9 where R is a indicator of values below 10pF and have nothing to do with resistance. 3R9 would be 3.9pF.
Table 1 – Capacitor codes with letters and tolerances
3rd number | Multiply with | Letter | Tolerance |
0 | 1 | D | 0.5pF |
1 | 10 | F | 1% |
2 | 100 | G | 2% |
3 | 1,000 | H | 3% |
4 | 10,000 | J | 5% |
5 | 100,000 | K | 10% |
6 | 1,000,000 | M | 20% |
7 | Not used | M | 20% |
8 | 0.01 | P | +100%/-0% |
9 | 0.1 | Z | +80%/-20% |
Table 2A – Electronic Industries Alliance (EIA) – DC voltage code table
0E = 2.5 VDC | 2A = 100 VDC | 3A = 1 kVDC |
0G = 4.0 VDC | 2Q = 110 VDC | 3L = 1.2 kVDC |
0L = 5.5 VDC | 2B = 125 VDC | 3B = 1.25 kVDC |
0J = 6.3 VDC | 2C = 160 VDC | 3N = 1.5 kVDC |
1A = 10 VDC | 2Z = 180 VDC | 3C = 1.6 kVDC |
1C = 16 VDC | 2D = 200 VDC | 3D = 2 kVDC |
1D = 20 VDC | 2P = 220 VDC | 3E = 2.5 kVDC |
1E = 25 VDC | 2E = 250 VDC | 3F = 3 kVDC |
1V = 35 VDC | 2F = 315 VDC | 3G = 4 kVDC |
1G = 40 VDC | 2V = 350 VDC | 3H = 5 kVDC |
1H = 50 VDC | 2G = 400 VDC | 3I = 6 kVDC |
1J = 63 VDC | 2W = 450 VDC | 3J = 6.3 kVDC |
1M = 70 VDC | 2J = 630 VDC | 3U = 7.5 kVDC |
1U = 75 VDC | 2I = 650 VDC | 3K = 8 kVDC |
1K = 80 VDC | 2K = 800 VDC | 4A = 10 kVDC |
Table 2B – Electronic Industries Alliance (EIA) – AC voltage code table
2Q = 125 VAC | 2T = 250 VAC | 2S = 275 VAC |
2X = 280 VAC | 2F = 300 VAC | I0 = 305 VAC |
L0 = 350 VAC | 2Y = 400 VAC | P0 = 440 VAC |
Q0 = 450 VAC | V0 = 630 VAC |
Here is a list of common capacitors and a scale between the different grades of the Farad SI unit.
Table 3 – Capacitor code table
pico-farad (pF) | nano-farad (nF) | mikro-farad (mF, uF or mfd) | Capacitor code |
1 pF | 0.001 nF | 0.000001 uF | 010 |
1.5 pF | 0.0015 nF | 0.0000015 uF | 1R5 |
2.2 pF | 0.0022 nF | 0.0000022 uF | 2R2 |
3.3 pF | 0.0033 nF | 0.0000033 uF | 3R3 |
3.9 pF | 0.0039 nF | 0.0000039 uF | 3R9 |
4.7 pF | 0.0047 nF | 0.0000047 uF | 4R7 |
5.6 pF | 0.0056 nF | 0.0000056 uF | 5R6 |
6.8 pF | 0.0068 nF | 0.0000068 uF | 6R8 |
8.2 pF | 0.0082 nF | 0.0000082 uF | 8R2 |
10 pF | 0.01 nF | 0.00001 uF | 100 |
15 pF | 0.015 nF | 0.000015 uF | 150 |
22 pF | 0.022 nF | 0.000022 uF | 220 |
33 pF | 0.033 nF | 0.000033 uF | 330 |
47 pF | 0.047 nF | 0.000047 uF | 470 |
56 pF | 0.056 nF | 0.000056 uF | 560 |
68 pF | 0.068 nF | 0.000068 uF | 680 |
82 pF | 0.082 nF | 0.000082 uF | 820 |
100 pF | 0.1 nF | 0.0001 uF | 101 |
120 pF | 0.12 nF | 0.00012 uF | 121 |
130 pF | 0.13 nF | 0.00013 uF | 131 |
150 pF | 0.15 nF | 0.00015 uF | 151 |
180 pF | 0.18 nF | 0.00018 uF | 181 |
220 pF | 0.22 nF | 0.00022 uF | 221 |
330 pF | 0.33 nF | 0.00033 uF | 331 |
470 pF | 0.47 nF | 0.00047 uF | 471 |
560 pF | 0.56 nF | 0.00056 uF | 561 |
680 pF | 0.68 nF | 0.00068 uF | 681 |
750 pF | 0.75 nF | 0.00075 uF | 751 |
820 pF | 0.82 nF | 0.00082 uF | 821 |
1000 pF | 1 / 1n / 1 nF | 0.001 uF | 102 |
1500 pF | 1.5 / 1n5 / 1.5 nF | 0.0015 uF | 152 |
2000 pF | 2 / 2n / 2 nF | 0.002 uF | 202 |
2200 pF | 2.2 / 2n2 / 2.2 nF | 0.0022 uF | 222 |
3300 pF | 3.3 / 3n3 / 3.3 nF | 0.0033 uF | 332 |
4700 pF | 4.7 / 4n7 / 4.7 nF | 0.0047 uF | 472 |
5000 pF | 5 / 5n / 5 nF | 0.005 uF | 502 |
5600 pF | 5.6 / 5n6 / 5.6 nF | 0.0056 uF | 562 |
6800 pF | 6.8 / 6n8 / 6.8 nF | 0.0068 uF | 682 |
10000 pF | 10 / 10n / 10 nF | 0.01 uF | 103 |
15000 pF | 15 / 15n / 15 nF | 0.015 uF | 153 |
22000 pF | 22 / 22n / 22 nF | 0.022 uF | 223 |
33000 pF | 33 / 33n / 33 nF | 0.033 uF | 333 |
47000 pF | 47 / 47n / 47 nF | 0.047 uF | 473 |
68000 pF | 68 / 68n / 68 nF | 0.068 uF | 683 |
100000 pF | 100 / 100n / 100 nF | 0.1 uF | 104 |
150000 pF | 150 / 150n / 150 nF | 0.15 uF | 154 |
200000 pF | 200 / 200n / 200 nF | 0.20 uF | 204 |
220000 pF | 220 / 220n / 220 nF | 0.22 uF | 224 |
330000 pF | 330 / 330n / 330nF | 0.33 uF | 334 |
470000 pF | 470 / 470n / 470nF | 0.47 uF | 474 |
680000 pF | 680 nF | 0.68 uF | 684 |
1000000 pF | 1000 nF | 1.0 uF | 105 |
1500000 pF | 1500 nF | 1.5 uF | 155 |
2000000 pF | 2000 nF | 2.0 uF | 205 |
2200000 pF | 2200 nF | 2.2 uF | 225 |
3300000 pF | 3300 nF | 3.3 uF | 335 |
4700000 pF | 4700 nF | 4.7 uF | 475 |
6800000 pF | 6800 nF | 6.8 uF | 685 |
10000000 pF | 10000 nF | 10 uF | 106 |
15000000 pF | 15000 nF | 15 uF | 156 |
20000000 pF | 20000 nF | 20 uF | 206 |
22000000 pF | 22000 nF | 22 uF | 226 |
33000000 pF | 33000 nF | 33 uF | 336 |
47000000 pF | 47000 nF | 47 uF | 476 |
68000000 pF | 68000 nF | 68 uF | 686 |
100000000 pF | 100000 nF | 100 uF | 107 |
330000000 pF | 330000 nF | 330 uF | 337 |
470000000 pF | 470000 nF | 470 uF | 477 |
680000000 pF | 680000 nF | 680 uF | 687 |
1000000000 pF | 1000000 nF | 1000 uF | 108 |
I hope you found all this information helpful. Please leave a comment with picture for help to identify a capacitor.