A B C D

READING VALUE AND MEASURING THE VALUE OF RESISTOR

A. Purpose

1. Determining the value of resistance of a resistor by reading the resistor color

ring

2. Using an ohmmeter to measure resistance of a resistor

B. Base of theory

Resistors are common elements of electrical networks and electronic circuits

and are ubiquitous in most electronic equipment. Practical resistors can be made of

various compounds and films, as well as resistance wire (wire made of a high-

resistivity alloy, such as nickel-chrome). Resistors are also implemented within

integrated circuits, particularly analog devices, and can also be integrated into hybrid

and printed circuits. To use it, we need to know some things, such as the materials

used, the resistance value, tolerance, and power dissipation behavior at high

frequency.

The most widely used material for making carbon resistors are superimposed

on a ceramic. Other materials are also used to create, among others, metal film

resistors and wire-wound.

In this lab activity, we only restrict the use made of the carbon resistor whose

value is fixed as shown in Figure 1 with ½ watt power capability.

Figure 1. Resistors form a ring of color that express the value of resistance

Carbon resistor color code painted on the resistor body to declare the value of

resistance. Resistance value can be read using the formula:

R=( A )(B )x 10C

With A, B, and C respectively declared value of the color ring on the body of the

resistor.

Color code used is:

No. Color Value

1 Black 0

2 Brown 1

3 Red 2

4 Orange 3

5 Yellow 4

6 Green 5

7 Blue 6

8 Purple 7

9 Gray 8

10 White 9

For example if A = Yellow, B = purple, and C = orange, so it means the

resistor has a resistance 47 x 103 Ohm.

C. Tools and matter

The tools and materials used in these experiments is

a. 20 pieces of carbon resistors with color codes different

b. Ohmmeter

c. circuit board

d. connecting cable

D. Step of experiment

a. Prepare all tools and materials

b. Series of resistors each resistor on the board sequentially.

c. Read the resistance value of each resistor by its color code.

d. Measuring the value of resistance at each resistor by using an ohmmeter.

e. Noting the results of observation-based.

f. Comparing the resistance values by reading the color codes and values based

on the measurement of resistance with an ohmmeter.

g. Analyzing data obtained from observations.

h. Perform steps 2-5 for as many as 20 times.

E. Data of experiment

No Read Resistance (Ω) Measured Resistance (Ω)

1 (68×101 )±(5% ) 680

2 (10×100 )±(5% ) 10.2

3 (82×101)±(5% ) 813

4 (47×100 )±(5 % ) 46.5

5 (56×103 )±(5% ) 55.3 × 103

6 (68×102 )±(5% ) 6700

7 (33×102 )±(5% ) 3250

8 (20×103 )±(5% ) 19.7 × 103

9 (30×102 )±(5% ) 2940

10 (12×101 )±(5% ) 118.8

11 (15×105 )±(5% ) 1489 × 103

12 (33×100 )±(5% ) 33

13 (18×102)±(5% ) 1785

14 (27×104 )±(5 % ) 277 × 103

15 (47×105 )±(5 % ) 5.5 × 105

16 (41×10−1 )±(5 % ) 5.2

17 (22×103)±(5% ) 21.8× 103

18 (13×103 )±(5% ) 11.78 × 103

19 (68×102 )±(5% ) 6740

20 (15×105 )±(5% ) 1466 × 103

F. Data Analysis Techniques

The data analysis technique used is to calculate the resistance value of

resistor color code corresponding to the ring and then compare it with the resistor

resistance value obtained from the experiment.

G. Data analysis

Here is a resistance value resistor readings manually and use the ohmmeter:

No Read Resistance (Ω) Measured Resistance (Ω)

1 (68×101 )±(5% )with tolerance 5% then the span

of resistance resistor is 71.4 x 101

until 64.6 x 101

680

Results are measured precisely in the range

71.4 x 101 until 64.6 x 101, so that the

readings are conducted in accordance.

2 (10×100 )±(5% )with tolerance 5% then the span

of resistance resistor is 10.5 x 100

until 9,5 x 100

10.2

Results are measured precisely in the range

10.5 x 100 until 9,5 x 100, so that the

readings are conducted in accordance.

3 (82×101)±(5% )with tolerance 5% then the span

of resistance resistor is 86.1 x 101

until 77.9 x 101

813

Results are measured precisely in the range

86.1 x 101 until 77.9 x 101, so that the

readings are conducted in accordance.

4 (47×100 )±(5 % )with tolerance 5% then the span

of resistance resistor is 49.35 x

100 until 44.65 x 100

46.5

Results are measured precisely in the range

49.35 x 100 until 44.65 x 100, so that the

readings are conducted in accordance.

5 (56×103 )±(5% )with tolerance 5% then the span

of resistance resistor is 58.8x 103

until 53.2 x 103

55.3 × 103

Results are measured precisely in the range

58.8x 103 until 53.2 x 103, so that the

readings are conducted in accordance.

6 (68×102 )±(5% )with tolerance 5% then the span

of resistance resistor is 71.4 x 102

until 64.6 x 102

6700

Results are measured precisely in the range

71.4 x 102 until 64.6 x 102, so that the

readings are conducted in accordance.

7 (33×102 )±(5% )with tolerance 5% then the span

of resistance resistor is 34.65 x

102 until 31.35 x 102

3250

Results are measured precisely in the range

34.65 x 102 until 31.35 x 102, so that the

readings are conducted in accordance.

8 (20×103 )±(5% )with tolerance 5% then the span

of resistance resistor is 21 x 102

until 19 x 102

19.7 × 103

Results are measured precisely in the range

21 x 102 until 19 x 102, so that the

readings are conducted in accordance.

9 (30×102 )±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

2940

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

10 (12×101 )±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

118.8

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

11 (15×105 )±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

1489 × 103

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

12 (33×100 )±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

33

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

13 (18×102)±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

1785

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

14 (27×104 )±(5 % )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

277 × 103

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

15 (47×105 )±(5 % )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

5.5 × 105

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

16 (41×10−1 )±(5 % )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

5.2

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

17 (22×103)±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

21.8× 103

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

18 (13×103 )±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

11.78 × 103

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

19 (68×102 )±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

6740

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

20 (15×105 )±(5% )with tolerance 5% then the span

of resistance resistor is 36,5 x 102

until 28,5 x 102

1466 × 103

Results are measured precisely in the range

36,5 x 102 until 28,5 x 102, so that the

readings are conducted in accordance.

H. Discussion

In the table we see data analysis in the table above Rread value is within range

(range) of the value Rmeasure, this means the value of the resistance R across the

resistor is appropriate as shown by the codes listed on the color characteristics of

these resistors, although there are some readings are not on the value range. This

happens because of errors in determining the zero point.

These errors occur since each will measure the resistance with the ohmmeter

must be calibrated in accordance with the level of reading ability. For example

starting from 10 ohm then 100 ohm. When moving the equipment to a value of 100

ohms, of course, there is little error in the laying ground zero. These errors affect the

observations.

I. Conclusion

1. Barriers to a resistor can be calculated by reading the color code rings

characteristic of the resistor. As for how to calculate the value of the

resistance of a resistor color code ring is AB x 10C ± D%.

Where :

A. The first ring; B. The second ring; C. The third ring; D. The fourth ring

2. Calculating the value of resistance in addition to the color code, it can be

done using the ohmmeter. Calculating resistance of a resistor using the

ohmmeter is done by placing the legs of the resistors in the circuit board

and pinned with wire ohmmeter and continued to read the digital numbers

on the ohmmeter.