Resistors
Resistors are passive electronic components.
Identification
Resistors' values are shown on the resistor, coded in a series of colored bands.
The resistors in labs here in Pratt are almost all 5% resistors or 1% resistors. That is, their actual values are either are guaranteed to be within 5% or 1% of the nominal, or labeled value.
The 5% resistors have three bands showing their value: two significant figures, and then the number of zeros.
The 1% resistors have four bands showing their value: three significant figures, and then the number of zeros.
For most of the resistors found around here, the last band will indicate the tolerance. For 5% resistors, the tolerance band will be the fourth band and will be the color gold. For 1% resistors the tolerance band will be the 5th band and will be brown.
In which order do you read the bands--left to right or right to left? Good question! You must use your intuition here. On 5% resistors, this is easy: the first significant figure will never be gold. If you read a 1% resistor and come up with an unlikely number, then you're probably reading it backward. Also, the first band is closer to the edge than the last band; on resistors with bulges at the ends, the first band is the one on the bulge.
"three band" (usually 5%) resistor color code:
| Color | 1st band | 2nd band | 3rd band (multiplier) | 4th band (tolerance) |
|---|---|---|---|---|
| Black | 0 | 0 | ×100 | |
| Brown | 1 | 1 | ×101 | ±1% (F) |
| Red | 2 | 2 | ×102 | ±2% (G) |
| Orange | 3 | 3 | ×103 | |
| Yellow | 4 | 4 | ×104 | |
| Green | 5 | 5 | ×105 | ±0.5% (D) |
| Blue | 6 | 6 | ×106 | ±0.25% (C) |
| Violet | 7 | 7 | ×107 | ±0.1% (B) |
| Gray | 8 | 8 | ×108 | ±0.05% (A) |
| White | 9 | 9 | ×109 | |
| Gold | ×10-1 | ±5% (J) | ||
| Silver | ×10-2 | ±10% (K) | ||
| None | ±20% (M) |
"four band" (usually 1%) resistor color code:
| Color | 1st band | 2nd band | 3rd band | 4th band (multiplier) | 5th band (tolerance) |
|---|---|---|---|---|---|
| Black | 0 | 0 | 0 | ×100 | |
| Brown | 1 | 1 | 1 | ×101 | ±1% (F) |
| Red | 2 | 2 | 2 | ×102 | ±2% (G) |
| Orange | 3 | 3 | 3 | ×103 | |
| Yellow | 4 | 4 | 4 | ×104 | |
| Green | 5 | 5 | 5 | ×105 | ±0.5% (D) |
| Blue | 6 | 6 | 6 | ×106 | ±0.25% (C) |
| Violet | 7 | 7 | 7 | ×107 | ±0.1% (B) |
| Gray | 8 | 8 | 8 | ×108 | ±0.05% (A) |
| White | 9 | 9 | 9 | ×109 | |
| Gold | ×10-1 | ±5% (J) | |||
| Silver | ×10-2 | ±10% (K) | |||
| None | ±20% (M) |
5% Resistor Standard Values
| 10 | 11 | 12 | 13 | 15 | 16 | 18 | 20 | 22 | 24 | 27 | 30 |
| 33 | 36 | 39 | 43 | 47 | 51 | 56 | 62 | 68 | 75 | 82 | 91 |
1% Resistor Standard Values
| 100 | 102 | 105 | 107 | 110 | 113 | 115 | 118 |
| 121 | 124 | 127 | 130 | 133 | 137 | 140 | 143 |
| 147 | 150 | 154 | 158 | 162 | 165 | 169 | 174 |
| 178 | 182 | 187 | 191 | 196 | 200 | 205 | 210 |
| 215 | 221 | 226 | 232 | 237 | 243 | 249 | 255 |
| 261 | 267 | 274 | 280 | 287 | 294 | 301 | 309 |
| 316 | 324 | 332 | 340 | 348 | 357 | 365 | 374 |
| 383 | 392 | 402 | 412 | 422 | 432 | 442 | 453 |
| 464 | 475 | 487 | 499 | 511 | 523 | 536 | 549 |
| 562 | 576 | 590 | 604 | 619 | 634 | 649 | 665 |
| 681 | 698 | 715 | 732 | 750 | 768 | 787 | 806 |
| 825 | 845 | 866 | 887 | 909 | 931 | 953 | 976 |
Use
Questions
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