3 Phase Changeover Switches

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Three-phase changeover switches are essential components of electrical systems, as they transfer loads between two power sources. In many cases, this is between your main electricity supply and a backup diesel generator.

While 3-phase switches might not seem like a big deal, they reduce operational downtime safely and reliably.

We have a range of 3 Phase Changeover Switches available to deliver seamless and reliable power backup when you need it most.

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The Types of 3 Phase Changeover Switches

Two main types of 3-phase changeover switch are available: Manual and Automatic. Both have advantages, but your choice ultimately depends on your budget and personal preferences.

Manual Changeover Switches

Manual changeover switches are beneficial when looking for a cost-effective solution or where power outages are rare. They require you to manually activate a rotary handle or lever to transfer loads between your main power source and the generator.

Residential properties and small businesses can use manual switches because they’re more affordable and are easier to install. However, a person will need to be physically present to ensure the load transfers.

Automatic Changeover Switches (ATS)

Automatic changeovers – also known as automatic transfer switches – offer protection against operational downtimes. ATS switches use a control circuit that detects power outages and automatically switches from your main electricity supply to the backup source.

However, they’re usually more expensive and are complicated to install. However, they’re ideal for large industrial businesses, data centres, and hospitals with critical life-saving equipment.

How Does a 3 Phase Changeover Switch Work?

A 3-phase changeover switch with a standby generator follows a distinct process. While single-phase transfer switches have one connection wire for small-scale operations, three-phase switches use three wires for homes and businesses with extensive power needs.

The switch will stay in the background when your main power supply is available. However, if you lose access to the main supply, the switch works as follows:

  • Detection: Both manual and automatic switches will identify when the power supply isn’t available.
  • Transfer: The switch will safely disconnect the circuits from your mains supply and transfer the connection to the backup generator, ensuring you can power equipment and appliances. Automatic switches will do this instantly, while manual switches require human intervention.
  • Restoration: When your main power supply becomes available again, an ATS will instantly switch back to it, while you’ll need to trigger the manual restoration process.

The switches also take safety precautions by including mechanisms that reduce the risks of power back-feeding (when electricity currents flow from your generator into the main supply).

This enhances health and safety while also protecting your vital equipment.

The Applications of 3 Phase Changeover Switches

3-Phase switches are ideal for various applications with medium to large-scale power needs. For example, a small residential home or office may be best with a single-phase changeover switch, but 3-phase switches are best for the following applications:

  • Industrial Businesses: Factories and processing plants often power heavy-duty equipment, but large diesel generators can ensure your operations continue. Adding an automatic three-phase switch minimises operational downtime.
  • Emergency Services: Hospitals and healthcare facilities rely on life-saving equipment to ensure patients receive the right care.
  • Data Centres: Even a small amount of operational downtime can result in data breaches, but an ATS ensures an instant transfer between power sources.
  • Commercial Buildings: While single-transfer switches are fine for small businesses, large commercial sites can benefit from a three-phase switch.

Installation and Safety Guidelines

Installing a changeover switch is an intensive step-by-step process that requires electrical expertise. For this reason, we recommend using a specialist service. Here’s how the process works:

  • Assessment: You’ll need to understand the total electrical load before you select a changeover switch product. Every switch should have a correct current and voltage rating to ensure that it can handle your maximum load.
  • Isolation: The installation service will disconnect your power supplies before beginning the installation, preventing potential health and safety issues.
  • Wiring: There are three sets of terminals with changeover switches: The main supply, generator supply, and load output. The professional will connect them according to the wiring diagram provided by your manufacturer. They’ll also label and colour code the labels.
  • Earthing & Testing: Effective earthing prevents damage to your equipment and electric shocks. Once everything is connected, the installation service will check to see whether there’s a smooth transition between your main and backup power supply.

Get Support From Solent Power

Solent Power specialises in helping homes and businesses streamline their power needs and ensure backup support. We offer a range of services, including diesel generator sales, delivery and installation support, ensuring compliance with CE and IEC standards.

Our experts can also help you find the right 3-phase switch for your needs, and we offer an affordable diesel generator maintenance service.

Please get in touch with us today for more information. We’ll discuss your options and find the right changeover switch for your needs.

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FAQ

What is a 3-phase changeover switch used for?

Three-phase changeover switches transfer power between one supply and another. They’re intended to ensure a continuous power supply when outages occur.

While manual switches might result in a short delay, an ATS transfers the load instantly, which prevents operational downtime for businesses and ensures homes don’t lose lighting or the ability to use appliances.

What’s the difference between manual and automatic switches?

Manual switches need human intervention to change between loads, while automatic switches operate alone. So, in the event of an outage, an ATS will provide immediate support. However, the best option for you depends on your budget and power needs.

Many homes and small businesses use manual switches, but large companies with time-sensitive equipment are best off with automatic switches.

Can I use it with diesel generators?

Yes, 3-phase switches are compatible with diesel generators, and they can improve the transition between power supplies. We offer a range of switches and diesel generators and can help you order the right products for your needs. 

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