How to test a relay with a multimeter?
The main reason for testing a relay is to find out if it is a good or bad one.The easiest way to find this is to use a multimeter with an ohmmeter setting and check its terminals.In this article, we will see how resistance readings are used to determine if the relay you are using is a good or bad one.
We need to check the resistance of the coil to see if it is good or bad.We can use resistance knowledge to find out if the relay is a good one or not.
The first thing to do is to search on the internet for that particular relay.The coil resistance and tolerance value can be found in that datasheet.The second step is to find the resistance value of a coil with a multimeter.
If you measure the actual relay coil terminals with a multimeter, you should get the values between 350 and 450.If your relay is faulty, you have to replace it.
If you want to check the resistance with a multimeter, you need to connect the probes to the two terminals of the relay coil.The relay coil has resistance.We are finding resistance, so the polarity of probes doesn't matter.
You can use this method as well.In this technique you check the three contacts of Relay, in these contacts the procedure is the same, we will measure the resistance of these contact with a multimeter.
If the value of NC contact is less than 0, the Normally closed terminal is not working.
The reason for this is that when NC and COM are not connected there is a huge amount of impendence.
If the relay is working well or not, there are two ways to find its function.Both ways check the resistance of the relay's terminals.The first method of checking the terminal resistance is useful if you don't have any available and the second method is also useful when you are making a project based on a relay.
If you find any query regarding the post, feel free to comment down below.Thanks.
My car is 20 years old.I was wondering if my relays could be malfunctioning.
The rebuilt motor failed immediately after I put it in.The motor got hot and was wondering about the relay.