SPECIFICATION |
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| Type No. | WCF 12 / WCF 25 M | WCF 25 / WCF 33 / WCF 40/ WCF50 M | WCF 50 / WCF 100 M | WCF 100 / WCF 200 M | WCF 200 / WCF 300 M |
| Rated Power at 70’C | 0.125 W / 0.25 W | 0.25 W / 0.40 W / 0.50 W | 0.50 W / 1 W | 1 W / 2 W | 2 W / 3 W |
| Resistance Range (E 24 series) | 0.1 E to 10 Meg | 0.1 E to 10 Meg | 0.1 E to 10 Meg | 0.1 E to 10 Meg | 0.1 E to 10 Meg |
| Tolerance | ± 5% | ± 5% | ± 5% | ± 5% | ± 5% |
| Maximum working voltage at 70’c at normal air pressure | 200V | 250V | 350V | 500V | 500V |
| Maximum Over Load Voltage | 400V | 500V | 700V | 1000V | 1000V |
| Operating Temperature Range | -40ºC to + 150ºC | -40ºC to + 150ºC | -40ºC to + 150ºC | -40ºC to + 150ºC | -40ºC to + 150ºC |
| Dielectric Strength | 400V No break downΔR.max. ± 0.5% | 500V No break downΔR.max. ± 0.5% | 700V No break downΔR.max. ± 0.5% | 1000V No break downΔR.max. ± 0.5% | 1000V No break downΔR.max. ± 0.5% |
CARBON FILM RESISTORS
The WCF Series Carbon Film Resistors are manufactured using mechanised high vacuum carbonising plants. This ensures a stable resistive film. The resistors are insulated with layers of light brown lacquer. The WCF series offer a wide range of power ratings (0.125 W, 0.25W, 0.4W, 0.5W, 1W, 2W & 3W) with a tolerance of ± 5%. and TCR ±1000 ppm/ºC.

Description
CHARACTERISTICS
CHARACTERISTICS |
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| Terminal Strength | no damage Δ R max. ± 0.5% |
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| Resistance to soldering heat (350ºC) | Δ R max. ± 1% | |||||
| Solderability | good tinning no damage |
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| Temperature Cycling -40 ºC to ± 150 ºC |
Δ R max. ± 1% | |||||
| Life 1000 hours at Rated Power | Δ R max. ± 3% | |||||
| Short time overload | Δ R max. ± 1% | |||||
| Resistance to solvents | no damage | |||||
STANDARD
E 24 Series
| 10 | 11 | 12 | 13 | 15 | 16 | 18 | 20 | 22 | 24 | 27 | 30 |
| 33 | 36 | 39 | 43 | 47 | 51 | 56 | 62 | 68 | 75 | 82 | 91 |
DIMENSIONS (in mm)

| TYPE WCF 12 / WCF 25M | H = 26 ± 2 | L = 3.3 ± 0.2 | D = 1.7 ± 0.1 | d = 0.45 ± 0.05 |
| TYPE WCF 25 / WCF 33 / WCF 40M/ WC 50M | H = 26 ± 2 | L = 6.0 ± 0.4 | D = 2.2 ± 0.1 | d = 0.50 ± 0.05 |
| TYPE WCF 50 / WCF 100M | H = 26 ± 2 | L = 9.0 ± 0.5 | D = 3.2 ± 0.2 | d = 0.55 ± 0.05 |
| TYPE WCF 100 / WCF 200M | H = 26 ± 2 | L = 11 ± 1.0 | D = 4.3 ± 0.5 | d = 0.65 ± 0.05 |
| TYPE WCF 200 / WCF 300M | H = 26 ± 2 | L = 15 ± 1.0 | D = 5.0 ± 0.5 | d = 0.75 ± 0.05 |

| Colour | lst figure | 2nd figure | Multiplier | Tolerance |
|---|---|---|---|---|
| Black | 0 | 0 | 1 | |
| Brown | 1 | 1 | 10 | ± 1% |
| Red | 2 | 2 | 100 | ± 2% |
| Orange | 3 | 3 | 1,000 | |
| Yellow | 4 | 4 | 10,000 | |
| Green | 5 | 5 | 100,000 | ± 0.5% |
| Blue | 6 | 6 | 1,000,000 | ± 0.25% |
| Violet | 7 | 7 | 10,000,000 | ± 0.1% |
| Gray | 8 | 8 | ||
| White | 9 | 9 | ||
| Gold | 0.1 | ± 5% | ||
| Silver | 0.01 | ± 10% |
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