You are fully aware that a digital multimeter can measure a lot of things, not to mention you can use it in many different situations. That also indicates there is a possibility you are only taking advantage of the multimeter’s functionalities when you normally use your meter for one application.
One of the main functions many multimeters provide is the capability to measure resistance. In other words, resistance is the measurement of how simple it is for an electrical current to flow through a specific part of a circuit or a component.
Have you ever tried measuring resistance in your job? If yes, you may have already encountered infinite resistance. However, what is an infinite resistance on a digital multimeter? This post will strive to answer that question and talk about what resistance is in more detail and determine what the symbol for ohms on a multimeter is.
So, what is resistance?
As stated above, resistance is the difficulty or ease that an electrical current needs to flow through an electric circuit. Let’s try to compare it to water flowing through a pipe to better understand this concept.
For instance, the water is your electrical current. The pipe is the component of that electrical circuit. Water flows through it without any fuss as long as the pipe is in top shape. However, it can’t keep the full capacity of the water when the pipe is somewhat clogged.
You see, it works the same along with resistance in electricity. There will be hardly any resistance if a component is fully optimized for electricity to flow through. Take note that the opposite of resistance is conductance.
That’s the reason why conductors play a critical role in electricity. The power lines you can notice flowing through the landscape, and that is supported by high poles are conductors. It’s intended to take electricity from one point to another point.
You won’t find just conductors in an electrical circuit built in, but resistors as well. Such resistors have a thoroughly balanced level of resistance regulating the flow within the electrical circuit. They also make a good example of why you can measure resistance.
Just visualize if those resistors should have a set resistance. It will then allow you to measure that with your multimeter. Resistors are made to have a set tolerance of a particular amount of age and ohms, but other factors could have an effect on exact tolerance.
What are ohms? What is the symbol it uses on a multimeter?
We stated that resistors have a tolerance of a set number of ohms. In case you didn’t know, ohms are also famous for their Ω symbol. It is the unit in which you measure resistance, the same way you use the unit kilograms or pounds to measure weight.
Did you know that ohms are named after the great German physicist, Greg Ohm who first thought of the concept of resistance in electricity in 1827? Now, resistance plays an integral part in understanding electricity, and the ohmmeter can be seen on any good multimeter.
Are you trying to measure resistance? Then it means you measure ohms. For the sake of this article, we will try to limit measuring resistance to a real resistor, as you will find many other uses for measuring resistance. That makes the ohmmeter one of the most utilized functions on your digital multimeter.
How can you measure ohms on a digital multimeter?
You will need a digital multimeter that can measure resistance to measure ohms. Bear in mind that most of the multimeters you can find in the market today can measure ohms. Just make sure that you refer to the manual for your particular model to prepare your multimeter. This will help you understand where to put the test leads.
Take note as well that ohm is the basic unit of measurement, but you need to measure milliohms often. That is not a function that is normally seen on each multimeter.
After you have organized your multimeter and turned it on, it’s time you put a test lead on every component you like to test. When it comes to a resistor, you can put one test lead on every end and read the reading on display.
You will find some measurements that can appear on your display. Apart from the measurement, you are expected when you are testing a resistor with a 1,000 ohms resistance, you will find other measurements you can see appear on your screen. One of them is the infinite resistance or OL.
What’s the relationship of infinite resistance to ohms in a multimeter?
Do you notice the infinite resistance or OL symbol on your multimeter? It indicates there’s no electrical current flowing through the circuit you are measuring.
Let’s go back to our example of measuring resistance. Remember that you measure how much water flows through the pipe. A clogged pipe offers more resistance, and that’s why less water flows through. A completely clogged pipe that doesn’t allow water through at all has a very high resistance that is off the charts.
It works the same with electricity. If you measure resistance and there’s no flow, your multimeter has to assume the flow has been interrupted to the point the resistance is off the charts. Hence, unlimited resistance indicates the multimeter has measured a huge amount of resistance that there’s no power left.
However, that does not necessarily indicate the resistance is high. Bear in mind that the digital multimeter is measuring the resistance by measuring the electrical current’s flow. A lack of current could indicate a resistor is giving off that much resistance. Nonetheless, a more typical explanation for insufficient current is an open switch or broken connection.
Often, reading an infinite resistance on a multimeter is the outcome of a broken connection.
Final thoughts
You should take the time to understand the ins and outs of your multimeter. One of the crucial functions of this tool is measuring resistance. Now that you finally understand the symbol for ohms on a multimeter, how to measure resistance, and what to do when you come across OL, you are a bit geared to use this versatile tool in a wide array of scenarios.
