Automatic changeover switch using contactors:

This diagram shows how to make an automatic changeover switch using contactors. In this circuit diagram, we use a single-phase energy meter, 2 DP MCB ( Double Pole Miniature Circuit Breaker ), 2 magnetic contactors, and a power generator. First, we need to input power to the single phase energy meter, then from the energy meter to input power DP MCB, then input power to magnetic contactor connection from DP MCB, then input power to another DP MCB from the power generator, then input power to the contactors. Now it’s ready for use. If you want to know more about this circuit please check our youtube video below the post.


Diagram of Automatic changeover switch using contactors:

Automatic changeover switch using contactors

Components needed For this Project:

You can get the components from any of the sites below:

  1. Single Phase Energy Meter [See Buy Click Amazon]
  2. DP MCB 25A [See Buy Click Amazon]
  3. Magnetic Contactor 25A [See Buy Click Amazon]
  4. Single Phase Generator 2000W[See Buy Click Amazon]

*Please note: These are affiliate links. I may make a commission if you buy the components through these links. I would appreciate your support in this way!

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Components used to make the Automatic changeover switch using contactors:

01. Single Phase Energy Meter:

A Single-Phase Energy Meter is a sort of Watt-Hour meter. It consists of two Electromagnets. Single-Phase Energy Meter is also Popularly known as a watt-hour meter. 1 Magnet is called the shunt magnet Ml which is Mounted with a Pressure coil. The Pressure coil is a long coil Made of fine Copper wire that is connected across the Supply single-phase line. Single-phase energy meters are suitable for measuring single-phase AC current flow frequencies of 50/60 Hz, which are used for fixed indoor installation systems.

02. DP MCB:

DP MCB In 2 Pole MCB, switching & protection is affected in phases and the neutral. A Double Pole or DP Switch is a Switch that Controls 2 Circuits at the same time. In terms of Residential Switching, this Normally means it Switches the live and Neutral at the same time. In Layperson Terms, Double Pole switches or DP Switches are Exclusively Designed to Control 2 Different Electrical Circuits at the same time, which allows the Appliances to Isolate safely and reliably. Fan or light Combinations and Medical Equipment are some of the many applications for DP Electrical Switches and Electrical components.

03. Magnetic Contactor:

A magnetic contactor is an electromagnetic switching device. It is generally used for controlling 3-phase Motors. The operation of a magnetic contactor is similar to that of a Relay. but a relay is used for low-power or low-voltage connections, and a magnetic contactor is used for high-power or high-voltage connections. As soon as the supply is applied to the magnetic contactor coil. its normally open contacts are closed and normally closed contacts are opened and the associated devices are also operated. This is how a magnetic contactor works.

04. Power Generator:

An electric generator is a type of Electrical device that converts mechanical energy or power into electrical energy or power. However, dynamo generally refers to generators only. The first generator built was called a dynamo. This electrical device makes this conversion using the principle of kinetic electromagnetic energy generation. According to Farad is principle of electromagnetic induction, a dynamic electromagnetic induction is induced in a conductor when it passes through a magnetic flux.

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Frequently asked questions

What is the methodology of an automatic changeover switch?

The automatic power supply change-over switch is a device that links the load and mains power supply or the alternative supply together. This enables the use of either the mains power supply or an alternative source when there is an outage on the mains and source. This can either come in with three phases or a single phase.

What is the difference between manual and automatic changeover switch?

A manual transfer and switch, automatic transfer switches can be used with permanent power supply installed standby generators. That way, when your power supply is disrupted and your company is subject to blackouts, your generator will automatically kick on and supply an emergency backup power supply to your building.

What is the advantage of automatic switching?

An installed automatic switch will operate immediately in the event of blackouts, grid stutters, and any other interruption to your electricity. Automatic switches are very popular for Highly adaptive energy availability. Increased safety and process efficiency.

What is an auto changeover regulator?

Automatic Changeover Regulator automatically switches from an empty service cylinder to a full reserve cylinder, ensuring continuous gas flow to appliances. A highly visible full/empty indicator signals a refill.

What are the features of a changeover switch?

Thus, the changeover switch ensures continuity of supply to the load by alternating between normal and alternate supply. The switch is in the ON position with normal supply available at the outgoing terminals. The switch is in the ON position with an alternate supply available at the outgoing terminals.

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