The power relay is used in the electrical circuit for the protection of electrical circuits, electrical systems, and equipment.

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In any electrical system, the protection of the system always has the highest priority. Basically, a power relay can be defined as an electrical switch that allows the passage of electrical current when it is closed and interrupts it when it is open, but that is electrically operated, not manually.

The Chint tower relay is made up of a coil connected to a current. When the coil is activated, it produces an electromagnetic field that causes the power relay contact that is normally open to close and allows current to pass through a circuit to, for example, light a lamp or start a motor. When we stop supplying current to the coil, the electromagnetic field disappears, and the power relay contact reopens, leaving the electrical circuit that went to that lamp or motor without current.

Dmitry G, CC BY-SA 3.0, via Wikimedia Commons


There are different types of power relay:

Electromechanical relays- These relays have variants depending on the activation mechanism. They can be of the armature, moving core, reed or reed type, polarized relays, or three-pole relays.

Solid-state relays– Solid state relays, which are used in situations where there is continuous use of the relay contacts and a higher switching speed is required.

Timer or delayed action relay- With these relays, it is achieved that the connection or disconnection is made after a certain time.

Thermal relays- They are used to protect motors from overloads. They have metal sheets inside that deform more or less depending on the heat. If they reach a certain point of deformation because the heat of the motor has increased, they open the circuit and do not let the current pass.

Arduino relay- With an Arduino board, we can control a relay. We only have to connect the relay to one of the 5-volt pins that this board has. By programming the board, we can obtain interesting results to control lighting and motor start-ups.

Dmitry G, CC BY-SA 3.0, via Wikimedia Commons


A power relay is a switch that controls (opens and closes) an electromechanical circuit. The main operation of this device is to use the signal to establish or disconnect the signal and turn it on or off without human intervention. It has a wide variety of applications, as shown below:

The power relays are used to activate a circuit with considerable electricity consumption through a circuit of small power – 12 or 24 volts – that magnetizes the coil. Suppose you want to motorize a garage door or a farm entrance. For this, you will need a remote control that manages to activate through a receiver that small power load that starts the operation of the power relay: the coil will magnetize and close the electrical circuit that feeds the motor that serves to open the door. We can also use it to turn on machines and motors, lighting systems, etc.

Sometimes, we find lighting circuits that need a lot of power to function. By activating and deactivating them indirectly through the use of Chint Power Relay that operates with little power, we prevent possible risks and accidents.

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In the automotive industry, Chint Power Relay is also widely used to activate fans, windshield wipers, horns, windows, etc. The indicator relay allows the light to blink when activated and to emit the characteristic sound when it is turned on.

It is also used to control switches on automobile motors. A 230V AC power source is required to start an electric motor, but in rare cases/applications, you can start the motor with a DC supply voltage. In such cases, power relays can be used.

Power relays are used in Automatic stabilizers also. If the supply voltage differs from the rated voltage, a series of power relays detect voltage fluctuations and use switches to control the load circuit.

Conclusion: Power relays are used in televisions. Older receiver tubes The internal circuits in televisions run on direct current, but receiver tubes require very high AC voltage, and direct current can be used to drive receiver tubes with power relays.

Power relays can be used in traffic signal controllers and temperature controllers.