RESISTANCE

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RESISTANCE CONVERSIONS

Standard unit = Ohm (W)
 
  abohm ohm statohm
1 abW = 1 10-9 1.113 * 10-
1 statW = 109 1 1.113 * 10-12
1 statW = 8.987 * 1020 8.987 * 1011 1
 

RESISTOR MARKINGS
Three methods of resistor markings are predominant - color coding, numerical value coding and three-digit symbol coding. MIL-PRF-55342 assigns part numbers using alpha-numeric coding. Tolerance, temperature, package style and failure rate are integrated into some numbering schemes.
 
Color Coding
(3-Band and 4-Band Resistors)
Color 1st
Significant
Digit 		2nd
Significant
Digit 		3rd
Significant
Digit
(if used) 		Multiplier Tolerance Failure Rate Level
(% per 1000 hours)
None         ±20%  
Gold       0.01 ±10%  
Silver       0.1 ±5%  
Black 0 0 0 1    
Brown 1 1 1 10  ±1% M = 1.0%
Red 2 2 2 100  ±2% P = 0.1%
Orange 3 3 3 1000 (=1k)   R = 0.01%
Yellow 4 4 4 10k   S = 0.001%
Green 5 5 5 100k    
Blue 6 6 6 1000k    
Violet 7 7 7      
Gray 8 8 8      
White 9 9 9      

3-Band Example
4-Band Example
6 - 2 - 3 - Silver
62 * 103 W, 10%
62 * 1000 W, 10%
62 kW, 10%


 

 1 - 9 - 6 - 0 - Red
196 * 100 W, 0.1% Failure Rate
196 * 1 W, 0.1% Failure Rate
196 W, 0.1% Failure Rate


 

 

Numerical Value Coding
4 - 4 - 2 - 2
442 * 102 W
442 * 100 W
44 200 W
44.2 kv
 

3-Digit Symbol Coding

 (1%)

A = 100, B = 101, C = 102, D = 103, E = 104, R = 10-1, S = 10-2

Example: 

   1.00 W,    01S
  12.1 W,    09R
  165 W,     22A
  4.32 MW,  62E
Symbol W
01 100
02 102
03 105
04 107
05 110
06 113
07 115
08 118
09 121
10 124
11 127
12 130
13 133
14 137
15 140
16 143
Symbol W
17 147
18 150
19 154
20 158
2 162
22 165
23 169
24 174
25 178
26 182
27 187
28 191
29 196
30 200
31 205
32 210
Symbol W
33 215
34 221
35 226
36 232
37 237
38 243
39 249
40 255
41 261
42 267
43 274
44 280
45 287
46 294
47 301
48 309
Symbol W
49 316
50 324
51 332
52 340
53 348
54 357
55 365
56 374
57 383
58 392
59 402
60 412
61 422
62 432
63 442
64 453
Symbol W
65 464
66 475
67 487
68 499
69 511
70 523
71 536
72 549
73 562
74 576
75 590
76 604
77 619
78 634
79 649
80 665
Symbol W
81 681
82 698
83 715
84 732
85 750
86 768
87 787
88 806
89 825
90 845
91 866
92 887
93 909
94 931
95 953
96 976

A = 100, B = 101, C = 102, D = 103, E = 104, R = 10-1, S = 10-2

Example: 

   2%,    1.00 W,  S01
  5%,    1.00 W,  S25
  10%,  1.00 W,  S49
  5%,    510 W,   A42
  10%,  820 kW,  D60
2%
Symbol W
01 100
02 110
03 120
04 130
05 150
06 160
07 180
08 200
09 220
10 240
11 270
12 300
13 330
14 360
15 390
16 430
17 470
18 510
19 560
20 620
21 680
22 750
23 820
24 910
5%
Symbol W
25 100
26 110
27 120
28 130
29 150
30 160
31 180
32 200
33 220
34 240
35 270
36 300
37 330
38 360
39 390
40 430
41 470
42 510
43 560
44 620
45 680
46 750
47 820
48 910
10%
Symbol W
49 100
50 120
51 150
52 180
53 220
54 270
55 330
56 390
57 470
58 560
59 680
60 820

 

RESISTOR MARKINGS: MIL-PRF-55342

 
Designator for 0.1% Tolerance Resistance (W)
1A00 to 9A88 inclusive
10A0 to 98A8 inclusive
100A to 988A inclusive
1B00 to 9B88 inclusive
10B0 to 98B8 inclusive
100B to 988B inclusive
1C00 to 9C88 inclusive
10C0
1.00 to 9.88   inclusive
10.0 to 98.8   inclusive
100 to 988   inclusive
1 000 to 9 880   inclusive
10 000 to 98 800   inclusive
100 000 to 988 000   inclusive
1 000 000 to 9 880 000   inclusive
10 000 000      
Designator for 1% Tolerance Resistance (W)
1D00 to 9D76 inclusive
10D0 to 97D6 inclusive
100D to 976D inclusive
1E00 to 9E76 inclusive
10E0 to 97E6 inclusive
100E to 976E inclusive
1F00 to 9F76 inclusive
10F0
1.00 to 9.76   inclusive
10.0 to 97.6   inclusive
100 to 976   inclusive
1 000 to 9 760   inclusive
10 000 to 97 600   inclusive
100 000 to 976 000   inclusive
1 000 000 to 9 760 000   inclusive
10 000 000      
Designator for 2% Tolerance Resistance (W)
1G00 to 9G10 inclusive
10G0 to 91G0 inclusive
100G to 910G inclusive
1H00 to 9H10 inclusive
10H0 to 91H0 inclusive
100H to 910H inclusive
1T00 to 9T10 inclusive
10T0
1.00 to 9.10   inclusive
10.0 to 91.0   inclusive
100 to 910   inclusive
1 000 to 9 100   inclusive
10 000 to 91 000   inclusive
100 000 to 910 000   inclusive
1 000 000 to 9 100 000   inclusive
10 000 000      
Designator for 5% Tolerance Resistance (W)
1J00 to 9J10 inclusive
10J0 to 91J0 inclusive
100J to 910J inclusive
1K00 to 9K10 inclusive
10K0 to 91K0 inclusive
100K to 910K inclusive
1L00 to 9L10 inclusive
10L0
1.00 to 9.10   inclusive
10.0 to 91.0   inclusive
100 to 910   inclusive
1 000 to 9 100   inclusive
10 000 to 91 000   inclusive
100 000 to 910 000   inclusive
1 000 000 to 9 100 000   inclusive
10 000 000      
Designator for 10% Tolerance Resistance (W)
1M00 to 8M20 inclusive
10M0 to 82M0 inclusive
100M to 820M inclusive
1N00 to 8N20 inclusive
10N0 to 82N0 inclusive
100N to 820N inclusive
1P00 to 8P20 inclusive
10P0
1.00 to 8.20   inclusive
10.0 to 82.0   inclusive
100 to 820   inclusive
1 000 to 8 200   inclusive
10 000 to 82 000   inclusive
100 000 to 820 000   inclusive
1 000 000 to 8 200 000   inclusive
10 000 000      
 

 

STANDARD RESISTOR VALUES
Standard base resistor values are given in the following tables for the most commonly used tolerances (1%, 5%, 10%), along with typically available resistance ranges. To determine values other than the base, multiply the base value by 10, 100, 1 000 or 10 000.
Example: Calculations indicate the need for a 355 kW resistor and a tolerance of 1% .
Look in the 1% table and select the 35.7 value (the nearest available standard value). Multiply by 10 000 to convert to 357 kW.
1% Standard Values
Decade multiples are available from 10.0 W through 1.00 MW
(also 1.20 MW, 1.50 MW, 1.80 MW, 2.00 MW and 2.20 MW)
10.0 10.2 10.5 10.7 11.0 11.3 115 11.8 12.1 12.4 12.7 13.0
13.3 13.7 14.0 14.3 14.7 15.0 15.4 15.8 16.2 16.5 16.9 17.4
17.8 18.2 18.7 19.1 19.6 20.0 20.5 21.0 21.5 22.1 22.6 23.2
23.7 24.3 24.9 25.5 26.1 26.7 27.4 28.0 28.7 29.4 30.1 309
31.6 32.4 33.2 34.0 34.8 35.7 36.5 37.4 38.3 39.2 40.2 41.2
42.2 43.2 44.2 45.3 46.4 47.5 48.7 49.9 51.1 52.3 53.6 54.9
56.2 57.6 59.0 604 61.9 63.4 64.9 66.5 68.1 69.8 71.5 73.2
75.0 76.8 78.7 80.6 82.5 84.5 86.6 88.7 90.9 93.1 95.3 976
 

5% Standard Values
Decade multiples are available from 10 W through 22 MW
10 11 12 13 15 16 18 20 22 24 27 30
33 36 39 43 47 51 56 62 68 75 82 91
 

10% Standard Values
Decade multiples are available from 10 W through 1 MW
10 12 15 18 22 27 33 39 47 56 68 82
 

Standard unit = Ohm (W)
 
  abohm ohm statohm
1 abW = 1 10-9 1.113 * 10-
1 statW = 109 1 1.113 * 10-12
1 statW = 8.987 * 1020 8.987 * 1011 1