How to use a multimeter to test resistors
Note: Due to the existence of a wide variety and types of multimeters we will explain the most common method for all of them. This is the case for the analog multimeter, although it can also be used with the digital multimeter.
The range selector of resistance is different from of the voltage and the current. When the function selector is in ohms, the measured result is multiplied by the factor that is showed in the range (look at the picture)
Common ranges are: Rx1, Rx10, Rx100, Rx1K, Rx10K, Rx1M, where:
- K means Kilohms
- M means Megaohms
For example (Look at the yellow color on the picture)
The multimeter scale shows 4.7 and the range is: x 1000 or x 1K. The multimeter would be measuring a resistor value of 4.7 x 1000 = 4700, or 4.7 K (Kilohms). It is very important to choose the right function and the range before making a measurement. If you make a mistake you can damage the multimeter.
Additionally, the analog multimeters have two knobs that allow you to adjust the needle to zero (rest position) and the other to adjust the reading of zero ohms (0).
To accomplish this you have to proceed as follows:
- put the function selector in Ohms
- put in the range selector in x 1
- join the test leads
At the end of the preceding process, the needle should be at 0 ohms, if not an adjustment have to be done with the knob, touching the multimeter leads together and checking that it reads 0 ohms.