For a plumber or an electrician, an Ohm meter is a constant companion that needs to be used quite frequently. For safety and functional purposes, measuring electrical resistance is very important. This is where the Ohm meter comes in.
Even if you are not a professional plumber or electrician, you may want to learn how to use an Ohm meter. Continue reading to find out all about the process of using an Ohm meter. Once you are done, you surely will be able to use it around your house successfully.
What Is An Ohm Meter?
First things first, let us develop a detailed and much necessary understanding of what an Ohm meter is. The name Ohm meter comes from its measurement unit, which is presented by the Greek letter Omega.
Based on the measurement power, there are two types of Ohm meter – micro Ohm meter and meg- Ohm meter. Micro Ohmmeter works perfectly for measuring very low electrical resistance. A mega OHM meter- also called a megOhmmeter, is used to test and measure very high electrical resistance values.
What Can An OHM Meter Do?
In order to learn to use an OHM meter, we first need to understand what an OHM meter can do. An OHM meter is a tool that can be proven to be useful in many scenarios. Whether the electrical resistance is low or high, it needs to be checked regularly and made sure it does not cross a certain threshold.
By using an OHM meter, you can measure dangerously low resistance that is likely to cause a short circuit. Short circuits often cause accidents, so detecting beforehand will surely ensure more safety for you and your loved ones.
On the other hand, too high electrical resistance could mean an overheated or even a damaged conductor.
Top OHM Meters
You do not have to buy brand-name OHM meters, but it is always nice to have some knowledge about the popular ones. If you are looking for some budget options, some good brands are – Etekcity, Multimeter, Digiflex, etc.
In the premium section, some good options are – Amprobe, Hioki, Fluke, etc. Amprobe and Fluke also have some nice cheaper options.
How to Use an OHM Meter?
Without further ado, let us talk about how to use an OHM meter. Take a look at our detailed step-by-step guide below to understand more about this process.
a) Setting Up The OHM Meter
The first thing you will have to do is set up your OHM meter. Some OHM meters are battery-operated, while some need to be plugged into electricity. Start by plugging in the Meter and making sure that it is plugged in or batteries are inside it.
b) Do A Test Run
Conduct a test run to make sure that everything is well with the OHM meter. The most common way to do this is to touch the two tester ends of the OHM detectors together and make sure that the meter reading is zero.
Users also conduct a test run with a resistor and even with household items that can pass electricity, such as some fruits, pencils, copper wire, etc.
c) Disconnect and Turn Off
This part is extremely important for the safety of you and your loved ones. No matter what, always turn off and disconnect the device or the circuit you will be testing. If you do not, your OHM meter has a chance to get damaged, and worst of all, you may get injured or hurt.
For devices that have capacitors, simply disconnecting will not be enough. Not to mention, keeping the device or circuit turned on will lead to inaccurate meter readings.
d) Know Your Numbers
Before testing and measuring, you need to know the resistance range of the circuit or the device you will be testing. You can find this range on a service manual and even online.
Make sure you select your range and your scale accordingly. Your Meter should be set lower than the resistance score on the device. Depending on your device, you may have to set a unit in Ohm, megOhm, or kilOhm. You can check the manufacturer’s manual or check online.
e) Put the Meter to the test
Now it is time to test resistance with your OHM meter. Simply touch the two ends of the Meter to the two ends of the item you are testing. It could be a switch, a circuit, or even a device.
Reading the OHM Meter
After you are done learning how to use the OHM meter to measure resistance, it is now time to learn how to read the numbers. OHM meters are of two types – digital and analog.
The digital Meter displays the number while the analog one uses a needle meter or scale to indicate the number. After reading the number, compare it with the prescribed range for the item you are testing.
Digital meters are far easier to use and read as they directly display the number. Check if there is a K or an M beside the Omega Symbol. An omega symbol with a K means 1000 Ohms while an omega symbol with M means 1,000,0000 Ohms.
Both too low and too high OHM are bad for your device and your electric line. Always remember that the appropriate range of OHM numbers varies depending on your test subject – a device or a circuit. If the numbers you read are below or above the prescribed range, do not forget to necessary steps and stay cautious.
Some Necessary Tips
While using the OHM meter, you need to keep some tips and guides in mind that will help you use the device more freely. Let us take a look at some such tips.
- You should always turn off your OHM meter after you are done using it for both digital and analog ones.
- If you test frequently and test several different kinds of devices, it is better that you have more than one type of OHM meter.
- No matter what, always remember to turn off and disconnect the device you are testing.
- Consult the device manual to find out the appropriate resistance of the item you are testing
- Last but not least, keep your Meter away from children.
Frequently Asked Questions
1. What does it mean when the OHM meter gets a zero(0) reading?
You get zero reading when you are testing the OHM meter by connecting two ends. This also means they did not measure anything. This step is generally carried out before doing the actual test.
2. Why is my OHM meter showing the sign ‘OL’?
OL means over the loop, and this indicates that your voltage range is set too low. To find out the proper voltage range, you can check the product manual or start your test with a lower range and test as you go.
3. What are the lowest and highest OHM values?
The lowest OHM value is zero, while the highest value is infinity.
4. What is a good OHM reading for a ground rod?
For a ground rod, there is no hard and fast value. Generally, the closer to zero it is, the better the value.
After reading our article, we hope you have learned all about how to use an OHM meter. No matter what, always stay safe at the workplace.
Also, if you have any opinion regarding the article, let us know in the comments.