You may be familiar with a multimeter. You have probably seen it with technicians or any other technical person around. I was like that as well, before the need arose for me to not just study it but learn to use it accurately.
How hard it is for electricity to flow through something, if it is very hard it means there is higher resistance.
A multimeter is what can be used to measure resistance, it sends a little electric current through the circuit. Just as there is the unit of measuring length, weight, and distance; the unit of measuring resistance with a multimeter is the ohm.
The ohms symbol is Ω (called omega- a Greek letter). (1)
The list of resistance measuring symbols is the following:
- Ω = Ohms.
- kΩ = Kilohms.
- MΩ = Mega ohms.
In this article, we will cover the measuring of ohms using a digital and analog multimeter.
Measuring Ohms with a Digital Multimeter
Steps to follow to complete resistance test procedure
- All power to the circuit to be tested be turned off.
- Ensure the component to be tested is separated from the complete circuit.
- The selector dial should be on Ω.
- The test lead and probes are to be connected to the terminals correctly. This is essential to get an accurate result.
- The window should be observed to get the Ω reading.
- Select the right range, which varies from 1ohm to megaohms (a million).
- Make a comparison of the results with the manufacturer’s Ω specification. Where the reading matches, resistance will not be an issue, however, if the component is a load, the resistance should match the manufacturer’s spec,
- Where the reading is overload (OL) or infinite(I), the component is open.
- If there is no further test to be done the meter should be put “off” and kept in a safe place.
Measuring Ohms with an Analog Multimeter
- Pick an item whose resistance you want to measure.
- Insert the probes into the right socket, and check for the colors or labeling.
- Find the range – this is done by observing the needle swings across the scale.
- Conduct the measurement- this is done by touching the opposite ends of the component with both leads.
- Read the results. If the range is set at 100ohms, and the needle stops at number 5, the result is 50ohms, which is 5 x the selected scale.
- Set the voltage at a high range, this is to prevent damage.
Wrapping Up
Measuring resistance with a multimeter be it digital or analog requires attention to get an accurate result. I am quite sure this article has helped you to learn steps to follow when using a multimeter to measure resistance. Why get a professional to do a simple check if you can! (2)
Take a look at some of our related articles below.
- How to measure amps with a multimeter
- How to test spark plug with multimeter
- How to test a circuit breaker with a multimeter
References
(1) Greek letter – https://www.britannica.com/topic/Greek-alphabet
(2) professional – https://www.thebalancecareers.com/top-skills-every-professional-needs-to-have-4150386
