How To Measure Resistor With Multimeter & Color Coding

Here is How To Measure Resistor With Multimeter & Color Coding To Cross Verify For Using in Circuit and DIY Electronics Works in Easy Steps. We have a basic article on breadboard power supply. After power supply, the next major important thing to learn is how to measure resistor with multimeter and color coding. There are bands painted on the resisters, that is basically for indicating their resistance. A multimeter is a very important tool and we highly suggest to buy even a very cheap multimeter. We are talking about through-hole, axial-lead resistors.

 

How To Measure Resistor With Color Coding

 

We have an Online Resistor Calculator, which is a Free Software; you can either use the demo or download the software from GitHub and open the index.html file on your browser to use if (you can use it offline in the second way). Also, you can calculate manually, which is the basis of the App. There is an international chart :

There are usually 4 color bands. Golden or Silver color is the reference point plus indicates the probability of error. If these are four bands |||| ; we will keep the golden or silver band towards the extreme right and read the band from the left hand side. If we have a resister with four bands – red, black, brown, golden ; then I will calculate in this way :

2 0 multiplied by 10 = 200

2 is for red.
0 is for black.
10 is for brown.

+/- 5% error for the golden band. Silver would give +/- 10% error. Yes, kid like calculation with no right logic, it is basically for enabling the peoples who has not much formal education but might handle the resisters (like for packaging) too. It was standardized in 1920s by the Radio Manufacturers Association. It was more for electrical works. Printing was not great at that time. It has many mnemonics, but is difficult to remember. It follows the visible light spectrum’s order. We are giving you somewhat easy way to remember :

Black (0) has no energy, brown (1) has a little more, white (9) has every color and grey (8) is like white. For red (2), orange (3), yellow (4), green (5), blue (6), violet (7) part, there is kind of rhyme. Too/Two Red is Three Orange which has Four Yellow Five Green Leaves with Six Blue Seven Violet Flowers. When we are saying Three as Multiplier, then it is 1 000.

It is hard to remember the numbers against the digits by a non-electrical, non-electronics person who otherwise read the Ohms Law. Plus a color blind can not see them.

 

How To Measure Resistor With Multimeter

 

We suggest to read the value from color coding first. Then we can use a multimeter to get near about the right value. We are talking about digital multimeter’s reading.

Plugs on Multimeter – there are usually two holes for the probes. 10A marked hole will not be used for this purpose. Use the remaining two.

Dial on Multimeter – move the dial to any of the suitable closer value, values starts from 200Ω and ends at 2MΩ. As because the resistors are of 5% difference in production, the resistor values are 5% apart.

Read approximate value from color coding or set to a medium value. Hold two probes against the resistor’s two legs on a flat non-conductive surface. If the reading comes in decimal like 0.19, then you can move the dial of multimeter to the next lowest value written on the multimeter. It will become like 187.

 

How To Measure Resistor in Circuit With Multimeter

 

It is very difficult to measure the resistor on circuit. The multimeter sources a small constant current and measures the voltage between the two probes using Ohm™s Law. If the current sourced by the multimeter goes through only one resistor, we can read the value of the resistor. But in a complex circuit, the current will flow everywhere, not just through the resistor of interest.

You can try by putting two new 10KΩ resistors in parallel on a flat surface. Then you’ll put the multimeter probes on both ends. The multimeter will read 5KΩ “ the equivalent resistance of two 10KΩ resistors in parallel. These multimeters are not exactly for measuring resistor on circuit. Desoldering is possibly the right method as there is some suspected error. Else you need to use the complex formula for parallel and series resisters.

You can see the color code, is not it? Defective resister is rare. Actually a Wheatstone bridge is better for complex circuit as we need precise measurement.

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