Practical - 20 :- Identify different types of capacitors from color code and typographic code

 

Objective

To learn how to read the codes on different capacitors and check if your reading is correct using a multimeter.

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Materials

• A collection of different capacitors (e.g., small ceramic discs, "boxy" film capacitors, and "can-shaped" electrolytic capacitors).

• A digital multimeter (DMM) that has a capacitance setting (marked with Cx or —|(—).

• A notebook and pen.

• Capacitor code charts (see below).

Procedure

This experiment has three easy steps: Inspect, Decode, and Verify.   

Step 1: Inspect & Sort (Visual ID)

First, look at your capacitors and sort them by their appearance. This tells you the capacitor type and gives a big clue about how to read it.

Color	1st Digit	2nd Digit	Multiplier (add zeros)
Black	0	0	$\times 1$ (0 zeros)
Brown	1	1	$\times 10$ (1 zero)
Red	2	2	$\times 100$ (2 zeros)
Orange	3	3	$\times 1000$ (3 zeros)
Yellow	4	4	$\times 10000$ (4 zeros)
Green	5	5	$\times 100000$ (5 zeros)

• Example: Bands are Yellow, Violet, Orange

  • Yellow: 4

  • Violet: 7

  • Orange: 3 (add 3 zeros)

  • Value: 47 + 000 = 47,000 pF (or 47 nF)

Step 3: Verify with the Multimeter (The Test)

Now, let's see if your decoding was correct.

1. Turn your multimeter dial to the capacitance setting (Cx or —|(—).

2. For Ceramic/Film (non-polarized): It doesn't matter which way you connect the probes. Touch one probe to each leg and read the value on the screen.

3. For Electrolytic (polarized):

   • SAFETY FIRST: Touch the two legs of the capacitor together for a second to discharge it.

   • CRITICAL: You must connect this correctly. Put the red (+) probe on the longer (positive) leg. Put the black (–) probe on the shorter (negative) leg (the one with the stripe).

4. Write down the measured value from the DMM.

Conclusion  

In your notebook, make a simple table to compare your results.

Capacitor Type (Visual)	Marking on Capacitor	My Decoded Value	Value from Multimeter
Ceramic Disc	104	100,000 pF (or 100 nF)	98.5 nF
Electrolytic Can	47µF 16V	47 µF	46.2 µF
Film (Box)	473	47,000 pF (or 47 nF)	45.9 nF
Old (Color)	Yellow, Violet, Orange	47,000 pF (or 47 nF)	48.1 nF