How to Read a Capacitor?

Reading capacitors labels is tricky business. Each family of capacitors uses its own unique labeling system. Some system are easy to understand, whereas others make use of misleading letters and symbols. The best way to configure out what a capacitors label means is to first figure out what family the capacitor belongs to. After that, try seeing if the capacitor label follows one of the convention like these :




Capacitors with small capacitances (less than 0.01 uF) do not pose much danger to humans. However, when the capacitances start exceeding 0.1 uF, touching capacitor leads can be a shocking experience. For example, large electrolytic capacitors found in television sets and photoflashes can store a lethal charge. As a rule, never touch the leads of large capacitors. If in question, discharge the capacitor by shorting the leads together with a screwdriver tip before handling it.

  OTHER INFO FOR POLYESTER CAPACITOR TYPE

 

 

• For JIS (Japan Industrial Standard), Korea, Taiwan

HJ Serie :

1. HJA type; dielectric substans is polyester film with aluminum foil electrode, color : green
2. HJT type; dielectric substans is polyester film with tin foil electrode, color : brown

• Specifications :

1. Temperature ranges : -40 ^o C to +85 ^o C
2. Voltage range : 1H code = 50 V, 2H = 500 V, 2A = 100 V, 2D = 200 V, 2G = 400 V
3. Capacitance standard value : 0.001 to 0.47 uF
4. Tolerance : J = 5 %, K = 10 %, M = 20 %
5. Breakdown Voltage = 2.5 times voltage level for 1 to 5 seconds
6. Isolation resistance = 20000 MOhm at 20 ^o C
7. Dissipation factor : max 1 % at 1 kHz
8. Pin connection : copper covered with tin

   

• Standard Value Table :

SYMBOL	VALUE (uF)		SYMBOL	VALUE (uF)
102	0.001		273	0.027
122	0.0012		333	0.033
152	0.0015		393	0.039
222	0.0022		473	0.047
272	0.0027		563	0.056
332	0.0033		683	0.068
392	0.0039		104	0.100
472	0.0047		124	0.120
682	0.0068		154	0.150
103	0.010		184	0.180
123	0.012		224	0.220
153	0.015		334	0.330
223	0.022		474	0.470

• For Philips Film Capacitor :

Specifications :

1. Range Value = 0.001 to 6.8 uF
2. Tolerance = 10 % to 20 %
3. Capacitance range = E - 12
4. Voltage Range = 100 V to 630 V
5. V_R (ac) at 50~60 Hz = 63 V to 220 V
6. Test Voltage = 1.6 times V_R
7. Temperature Range = -40 ^o C to +100 ^o C
8. Dissipation Factor at 10 kHz = less than 150 x 10 ^{- 4}
9. Isolation Resistance at 20 ^o C, C = 0.033 uF, R = 30000 MOhm (*), C = 0.33 uF, RC (MOhm x uF) = 10000 s, (*) Acception for 100 V version = R = 15000 MOhm, RC = 5000 s
10. Standard Value Table :
    
    

COLOR	VALUE	MULTIPLIER	TOLERANCE	VOLTAGE
Black	0	1	20 %
Brown	1	10		100 V
Red	2	100		250 V
Orange	3	1000
Yellow	4	10000		400 V
Green	5	100000
Blue	6			630 V
Violet	7
Grey	8
White	9		10 %

 

OTHER INFO FOR MK TYPE CAPACITORS

• Plastic metal alloy capacitors (like MK capacitors) can self recovery after breakdown. Very thin metal layer coat to plastic foil about 0.02 to 0.05 um. The arc with rise at breakdown will evaporate metal layer at the point without damage the dielectric. This happened for less then 10 usec. Capacitance lost can be disparage. Metal layer constructed to cylinder type or flat or arranged to stack. Metal syringe method that used to connect the wires guaranted all the roll are connected. That was made the MK capacitors had low inductance and low losses characteristic.
• DIN Code :

M = Metal layer ---------- M      K      S
K = Plastic -----------------------|        |
        * Third is the dielectric types : -----|
S = Polystyrene (MKS = MKY)
P = Polyprophylene (MKP)
C = Polycarbonate (MKC = MKM)
T = Polythereftalate (MKT = MKH)
U = Cellulose Acetate (MKU = MKL)