__Resistor Colour Code Notes__

Example 1.

Blue, Grey, Brown, Gold

Looking at the first band, Blue = 6. The second band is Grey which = 8. The third band is the most important. It tells us how many zero’s to add. Brown = 0 (1 zero)

Therefore the value of this resistor is 680 Ohms. This is written as 680R

EXERCISE A.

Determine the resistance values of these resistors, given their band colors.

1. Red, Org, Blu, Gld =

2. Brn, Blk, Grn, Sil =

3. Blu, Blk, Brn, Gld =

4. Yel, Vio, Red, Sil =

5. Grn, Brn, Yel Sil=

6. Wht, Blu, Blk, Sil =

7. Gry, Grn, Org, Gld =

8. Org, Org, Gld =

9. Vio, Red, Sil, Gld =

10. Brn, Red, Blk, Sil =

Exercise B.

Using the colour code calculate the value of the following resistors:

1. Brown, Black, Red Gold.

2. Yellow Violet, Yellow, Gold.

3. Brown, Black, Green, Gold.

4. Blue, Grey, Black, Gold.

5. Orange, White, Orange, Gold.

Given the resistor;

2.2k ± 10%

Step 1: Convert/change ALL values to ohms. Eg. 2.2k = 2200 Ω.

Step 2: Write Colour that represents 1st Digit.

Step 3: Write Colour that represents 2nd Digit.

Step 4: Circle/count the zeros and write the related 3rd colour.

Step 5: Write the colour for tolerance given.

Exercise 1

What are the colour bands on the following value resistors all of which have a 5% tolerance?

1. 22R

2. 10K

3. 10M

4. 470R

5. 33R

6. 220R

7. 3R3

Exercise 2

What are the colour bands on the following value resistors all of which have a 10% tolerance?

1. 22K

2. 10R

3. 10K

4. 470K

5. 33K

6. 220K

7. R33

Other methods/codes.

R = x 1

K = x 1 000

M = x 1 000 000

NB: the letters can be taken as the point “.” in the number.

EXAMPLES

680R = 680. x 1 = 680

2K2 = 2.2 x 1 000 = 2200

1M0 = 1.0 x 1000 000

Given the resistor. 470 +/- 5%

Step 1: Find/calculate the percentage.

Eg.

Blue, Grey, Brown, Gold

Looking at the first band, Blue = 6. The second band is Grey which = 8. The third band is the most important. It tells us how many zero’s to add. Brown = 0 (1 zero)

Therefore the value of this resistor is 680 Ohms. This is written as 680R

EXERCISE A.

Determine the resistance values of these resistors, given their band colors.

1. Red, Org, Blu, Gld =

2. Brn, Blk, Grn, Sil =

3. Blu, Blk, Brn, Gld =

4. Yel, Vio, Red, Sil =

5. Grn, Brn, Yel Sil=

6. Wht, Blu, Blk, Sil =

7. Gry, Grn, Org, Gld =

8. Org, Org, Gld =

9. Vio, Red, Sil, Gld =

10. Brn, Red, Blk, Sil =

Exercise B.

Using the colour code calculate the value of the following resistors:

1. Brown, Black, Red Gold.

2. Yellow Violet, Yellow, Gold.

3. Brown, Black, Green, Gold.

4. Blue, Grey, Black, Gold.

5. Orange, White, Orange, Gold.

__Using the colour code to find the colours for resistors:____Take a numerical resistor value and work out the correct colour bands__.Given the resistor;

2.2k ± 10%

Step 1: Convert/change ALL values to ohms. Eg. 2.2k = 2200 Ω.

Step 2: Write Colour that represents 1st Digit.

Step 3: Write Colour that represents 2nd Digit.

Step 4: Circle/count the zeros and write the related 3rd colour.

Step 5: Write the colour for tolerance given.

Exercise 1

What are the colour bands on the following value resistors all of which have a 5% tolerance?

1. 22R

2. 10K

3. 10M

4. 470R

5. 33R

6. 220R

7. 3R3

Exercise 2

What are the colour bands on the following value resistors all of which have a 10% tolerance?

1. 22K

2. 10R

3. 10K

4. 470K

5. 33K

6. 220K

7. R33

Other methods/codes.

R = x 1

K = x 1 000

M = x 1 000 000

NB: the letters can be taken as the point “.” in the number.

EXAMPLES

680R = 680. x 1 = 680

2K2 = 2.2 x 1 000 = 2200

1M0 = 1.0 x 1000 000

__TOLERANCE CALCULATIONS__Given the resistor. 470 +/- 5%

Step 1: Find/calculate the percentage.

Eg.

Step 2: Add the percentage value.

=> 470 + 24 = 494 Ω (max. value)

Step 3: Subtract the percentage value.

=> 470 - 24 = 446 Ω (min. value)

Step 4: Check if measured resistor falls within the max. and min. values.

Step 5: If Yes … resistor is GOOD.

If No … resistor is BAD.

=> 470 + 24 = 494 Ω (max. value)

Step 3: Subtract the percentage value.

=> 470 - 24 = 446 Ω (min. value)

Step 4: Check if measured resistor falls within the max. and min. values.

Step 5: If Yes … resistor is GOOD.

If No … resistor is BAD.