From the title, you get an idea about the topic. How to test a relay, most of the beginnings in electronics they don’t know the working and connections of relay and also don’t know how to check the relay is working properly or not. To help those people to learn testing relay.
How to test the working of a relay
The electromagnetic relay hard working based on the principle of electromagnetic attraction or electromagnetic force. The release is a type of magnetic switch is uses the magnet to create a magnetic field. Copper wires wounded on an iron core when a voltage is applied in the coil, the electromagnetic flux has occurred and the iron rod act as the magnet.
Electric relay types
- Electromagnetic relay
- Solid-state relay
- Hybrid relay
- Thermal relay
- Reed relay
Working of relay
Let’s starts with a brief introduction to the electric relay. Most commonly using relays is working based on the principle of the electromagnetic force. They are called electromagnetic relays. In this article, we discuss deeply the working and checking of these relays
The electromagnetic relay – from the name is very clear about the working principle. It uses an electromagnetic field to work. A coil ( copper wounded ) on the iron core. The resistance is about 100- 300 ohms ( assumption value based on the different relays). From the coils, two ends are connecting to a battery source this time the coil gets activated and creating a magnetic field to the iron rod.
This time the rod act as a magnet. The relay consists of contact switches if the iron rod gets activated nearest iron thicks are get stick to the rod. In that time the 2 switching connecting terminals are there it will change up and down. Then the connection to be changed in a two-way direction.
If the relay is on come contact with the down connection and if the charge released the relay connected to the upper connection. Normal state relay contact with the N/C. If the relay is on it will contact with N/O pin.
How to test relay using multi meter
- Take a multimeter and place the knobs on continuity checking mode.
- Without applying the voltage to the relay coil the connection will be with the N/C. Check the continuity, if yes the N/c pin works properly.
- Next applying a 12 v ( in this case I take 12 v relay so applying 12v DC ) check the continuity with N/O contact. If continuity is their the contact works perfectly.
- At last, check the relay coil resistance by measuring in the resistance mode on the multimeter and compare the coil resistance with the manufacturer.
4&3 is coil