How to Measure the Resistance of a Resistor

Two methods are normally used when measuring a resistor for resistance. The first method used is the resistor color code. This method offers a way to find the value without equipment at the cost of some accuracy. The second methods is using a multi-meter which is very precise, but require some more advance equipment.

Step 1: Find the Color Code to Be Used With Your Resistor.

Before you measure the resistance of a resistor, you need to know that manufacturers of the resistor ensure that the resistor is equal to a value with a variable range. Look online for the resistor color code to be used in the use color code chart. An example of this would be a 1000 ohm resistor with a range of +- 50 ohms.

Step 2: Find the Color Order.

The one used in the following examples will have three color stripes on one side, and one color stripe of the other side. While gold and silver are normally the way to tell the groups apart, there are some uncommon colors used that can confuse you without some practice using the color code.

Step 3: Read the Colors.

http://www.resistorguide.com/resistor-color-code/ The resistor mentioned above has four stripes on it. After finding the correct left to right reading of the stripes, you will be able to use the color code chart. They read Brown, Black, Red, and Gold.

Step 4: Use the Color Code Chart.

http://www.resistorguide.com/resistor-color-code/ Now using the color code you can tell the first digit 1, which is represented by brown. The second digit is 0, which is represented by black. The third digit is 2, which is represented by red, which will be used like 10^2. Now that this is complete you will combine the first two digit 1 and 0, making 10. Multipling that by the 10^2 will give you a value of 1000. The fourth and final value of gold means 5%, which means the maker of that resistor is letting you know that the ohm value is from 950-1050, or 5% off the value you found. If the resistor was 3000, then the range would be 2850-3150.

Step 5: Get a Multi-meter.

[[Image:20190307_143608.jpg|center]] https://www.allaboutcircuits.com/textbook/experiments/chpt-2/ohmmeter-usage/ The multi-meter is much faster then the color code and more accurate; however, it requires a very common but costly machine. There are many makes and models but the model used here is an Agilent module. On the module, the two plugs you will use are the top right red and middle right black plugs.

Step 6: Clip in the Resistor.

[[Image:20190307_143628.jpg|center]] [[Image:20190307_143738.jpg|center]]https://www.allaboutcircuits.com/textbook/experiments/chpt-2/ohmmeter-usage/ Which sides have the red or black clip is not important because resistors do not have polarity. Just attach the gator ends.

Step 7: Press the “Ω2W” Button.

[[Image:20190307_143746.jpg|center]] http://rfic.eecs.berkeley.edu/ee42/man/DMM%2034401A.pdf The reading will be giving in Kilo ohms. The reading is .996K ohms, which fits into the manufacturer’s promise of +-5%.