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Why Use Relay Switches

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Relays serve as interface components. They are used for different purposes. Relays have advantages and disadvantages. Let’s take a look each one-by-one.

If they are switching, separating, amplifying or multiplying relays, they are used for different purposes for industrial applications of control. They are characterized by specific features and can be found in an array of types available in the market. Relays offer many advantages for both the users and the systems. A few of them are:

Simple and efficient operation

The working principle for a relay’s operation is simple. The current that flows across the sensor generates magnetic fields that draw attention to an iron lever, which then changes the contact of the switch. It allows for controlling the device remotely. Relays are activated by the use of a small current. However it is able to switch huge circuits by using only a little of energy.

Circuit multiplication

Relays are able to switch multiple contacts simultaneously. The same voltage can be used to perform at least four distinct switching actions. Each output contact on relays is able to switch load circuits using different current and voltage levels.

Galvanic isolation

Relays are well-suited to provide safe galvanic isolation. Relays are a separate control circuit from the load circuit. Even in the event of failures or flash-overs, flash-overs between the contact and coils are not common. Relays aren’t just an instrument for control, but also one of the safety devices.

Conversion of voltage

Relays permit low voltage signals to control larger loads. For instance the 24 V DC 10 mA signal may serve as a switch for to a 220 V AC 16 A load. The larger loads could be controlled using just a little energy.

Accessory options

The whole relay body is comprised of an interface relay with pluggable plug, socket, holder, or functional module. Each component performs a different function and can help improve the efficiency that the relay.

For instance

A well-designed contact protection circuit could increase the life expectancy of contacts by 5-10 times over inductive loads that aren’t or are not properly protected. Freewheeling diodes are ideal for this use.

Contact switching for DC or AC

Many different types of relays can be utilized to switch AC as well as DC loads. They can be utilized in both DC and AC systems to protect DC and AC equipment. In addition, they are available in a variety of coil voltages and various functions that can be added as modules. Logistics and warehouses are crucial to the evaluation of total cost. By using relays, you will be able to drastically reduce the cost of logistics. By making use of products that have multiple voltage inputs, you will be able to reduce the length of your inventory.

Small size and low cost

The relay switch provides lower price with better performance and value by delivering important functions within a space-saving housing. Despite rising prices for raw materials they are cheap and effortlessly integrated in a range of circuits.

Connection to the terminal

There are a variety of sockets available for relays that can accommodate the demands of various scenarios, including those that require vibration. The design that is space-saving and the various connector terminals can greatly improve the panel’s installation. There are numerous connections for terminals, including spring, screw and fork types.

Some relays have been made to be used with PCB mounting, but you are able to connect wires directly to pins if you are careful to prevent melting the plastic housing of the relay.

Easy to set up and troubleshoot

Relays are simple to install by snapping them onto a DIN-rail. It is also possible to utilize jumping bars that make connecting simpler. Troubleshooting generally involves the removal or isolation of the device, and setting up a bench for testing the operation. The majority of relay models include a switch on the top that permits technicians to turn the contacts on and off even without electricity to the coil. This allows problems to be isolated on either the output or input side in a matter of seconds, and never require one wire to be removed.

Led indicator and test button

Relays show the location of the contacts using the use of an additional led. The state of the switch is evident to the naked eye. Certain types of relays have an additional test button. If it is activated, the contacts are activated. If it is removed, contact returns to previous condition.

High resistance

Relays have a very high resistance to voltage fluctuations. In RC modules, the voltage peak is compensated by the capacitor. Additionally, they can handle temporary overload on both the input and output sides , without being unable to function.

Long-lasting and maintenance-free

No matter the application or the environment Maintenance and repairs are essential and must be performed frequently. By using relays, you will significantly reduce the effort required. This makes the work simpler quicker, more efficient, economical, and more secure. The lifespan of an electrical quality relay is approximately one million operational cycles. It’s longer than other switches. However, in applications that require rapid switching the life span of the relay is reduced. It is important to take this into consideration.

Relays have disadvantages

Relays can have disadvantages for users and systems. They can be a problem for:

Contact wear

Because of their construction The relay modules are susceptible to wear and tear, both electrical and mechanical and this should be considered in the process of constructing relay circuits. being set up.

Use only for applications with low current

Relays can be used for controlling voltages of 12 V to the 230 V range (generally) and as switching currents ranging from six A and up A They can’t be used to switch high currents, like contactors.


They produce a lot sound with the activation as well as deactivation. It can be a nuisance when you have a lot of relays within control panels.

The operation is slow and has a low speed

Relays aren’t able to change their settings rapidly. The speed of operation of a relay is restricted due to the inertia mechanical the device. The time of their response as well as the number of switching cycles is less than transistors.

Change in character caused by age

Relay operation is impaired due to the ageing of the components as well as dust, which can cause false trips. As time goes on the springs and parts of the relay get weak.

Poor performance when working with high inrush electrical currents as well as microelectronic circuits

Relays aren’t able to handle high inrush currents like contactors can. The efficiency of relays is reduced when switching high inrush currents.

The coil in a relay requires an extremely high amount of current to be energized. A high coil consumption is one of the disadvantages in microelectronic circuits since they cannot be driven with a single circuit without additional circuitry.

Performance is poor in vibrating environments.

Many relays are specifically designed specifically for industrial use and have high-performance ratings. The conditions in railway vehicles vary vastly from those of typical industrial applications however. The extreme vibration, the frequent, and broad temperature cycles, as well as corrosion-prone, oily and damp conditions are all stress elements that include relays. This can result in poor efficiency when the industrial type of relays are utilized in vehicles.