Relays: Small but Terrible Electronic Device


In the world of electronics, relays, though small in size, play a big part in the operation of machines. Relays are basically used to switch small current that controls large current. It prevents you from having a direct contract with the main device that may be charged with high voltage. It is often compared to a remote which is used to make equipment work without the need to touch anything. Some large equipment and machines use larger relays to ensure practicability.

electromagnetic switches

What are Relays?

Relays are electromagnetic switches that is usually operated by a small electric current which in turn controls a larger electric current. Look at it like a lever. When you switch the relay on, the small current flows through it into a larger appliance or machine by using big current.

A relay is useful as there are sensors that can only product small currents due to its nature. Though small, these sensors are needed to drive bigger currents into the equipment. This means that relays can work in both ways – as switches or as amplifiers. As a switch, relays can readily turn anything on and off. As an amplifier, a relay can convert small currents into large currents.

How it is applied

To perfectly understand the function of a relay, think about how you switch on the head lights of your car. When you click the switch, a small current will flow on the coil towards the contactor. The relay then control a high power load which, in this case, the head lights.

Relays are actually used every day though we may not be able to notice it. It is applied at home, in business establishments and even on the streets. Take your refrigerator at home as an example. This particular appliance has fans and motors inside it. The one controlling these parts is the relay. It is responsible for cooling up the fridge and keeping your food fresh. Traffic lights are also controlled by relays. It has a switching component that operates it when changing lights. Garage doors that are automatically operated are good illustrations as to how relays apply in daily life.

Aside from making equipment and devices work, relays are also utilized to stop devices from working. This is especially handy for machines that contain higher amount of voltage which can cause great harm once they malfunction.

How it works

Power flows through the first circuit which activates the electromagnet and eventually generating a magnetic field. This field attracts a contact which in turn activates the second circuit. When the power is turned off, a spring gradually pulls the contact back to how it was originally situated.

Relays play important roles in your everyday life. It provides you convenience, comfort and ease. You are safe from danger because of how the relay electronically operates. You may not have been able to notice how it has greatly affected your activities but now that you understand how it works, maybe it’s time that you finally appreciate it no matter how small it is.