Keep Power Running with PROJOY Automatic Transfer Switch (ATS)

Power outages and voltage abnormalities can interrupt lighting, equipment, and other essential loads in homes, commercial buildings, and industrial facilities. An automatic transfer switch (ATS) helps reduce these interruptions by automatically switching the load from the main power supply to a backup power source when the normal power fails. For AC backup power systems, PROJOY Electric provides dual power automatic transfer switch solutions with fast transfer, manual and automatic operation, 2P/4P configurations, and compact DIN-rail installation, helping users build safer and more reliable backup power switching systems.

How Does a Dual Power Automatic Transfer Switch Work?

A dual power automatic transfer switch works between two power sources: the normal power supply and the backup power supply. In most systems, the normal power can be the grid, while the backup power can come from a generator, solar inverter, or energy storage system.

When the normal power is available, the ATS keeps the load connected to the main power source. If the main power fails, loses voltage, or becomes abnormal, the ATS automatically transfers the load to the backup power source. When the normal power returns, the ATS can switch the load back to the main power supply.

This process helps reduce power interruption without manual operation. For applications such as lighting, communication equipment, small commercial systems, and backup power distribution, an automatic transfer switch helps keep key loads powered when the main power source is not available.

Key Features of PROJOY Automatic Transfer Switch (ATS)

PC Class ATS for AC Power Systems

PROJOY Automatic Transfer Switch adopts a PC class design for AC 50/60Hz power systems with rated currents from 6A to 63A. It is designed to switch between normal power and backup power in low-voltage distribution systems, helping users build reliable backup power switching solutions.

Automatic and Manual Switching

The ATS supports both automatic and manual operating modes. During daily operation, the automatic mode continuously monitors the power supply and performs transfer without operator intervention. Manual operation provides additional flexibility during equipment inspection, maintenance, commissioning, or functional testing, allowing technicians to verify system performance safely.

Fast Transfer Within 50ms

Transfer speed directly affects the continuity of electrical loads. PROJOY Electric Automatic Transfer Switch provides a transfer time of no more than 50 milliseconds under specified operating conditions. This rapid response minimizes interruption during power source switching and supports continuous operation for sensitive electrical systems.

Flexible 2P and 4P Configurations

Different electrical systems require different pole configurations. PROJOY Electric offers both 2P and 4P ATS models, allowing customers to select products according to single-phase or three-phase power distribution requirements. The flexible configuration supports a broad range of installation environments and electrical applications.

Compact DIN-Rail Installation

Space-saving installation is an important consideration in modern electrical panels. The compact DIN-rail mounting design simplifies installation while reducing wiring complexity. Standard DIN-rail compatibility also makes replacement and future maintenance more convenient for installers and maintenance personnel.

2P and 4P Automatic Transfer Switch for Different Power Systems

Single Phase Automatic Transfer Switch (2P)

The 2P automatic transfer switch is designed for single-phase AC230V systems. It is commonly used in residential buildings, small commercial facilities, offices, communication equipment, and backup power applications where single-phase distribution is required. The compact structure allows easy integration into standard distribution boxes.

3 Phase Automatic Transfer Switch (4P)

The 4P automatic transfer switch is intended for AC400V three-phase power systems. It provides switching for three live conductors together with the neutral conductor, making it suitable for industrial equipment, commercial buildings, manufacturing facilities, and larger electrical distribution systems that require complete circuit isolation during transfer.

Automatic Transfer Switch (ATS) Selection Guide

Single Phase or 3 Phase ATS

The first step when selecting an ATS is determining whether the electrical system operates with single-phase or three-phase power. Single-phase systems generally use 2P transfer switches, while three-phase installations typically require 4P configurations to safely switch all necessary conductors and maintain system compatibility.

PROJOY Electric provides both 2P and 4P Automatic Transfer Switch models, allowing users to match the correct pole configuration with their electrical distribution system while maintaining reliable switching performance.

Rated Current and Voltage

The rated current and operating voltage should always match the electrical load and system requirements. Selecting insufficient current capacity may reduce service life, while excessive oversizing may increase unnecessary installation costs. Proper rating ensures safe long-term operation.

PROJOY Electric ATS products are available with rated currents from 6A to 63A. The 2P models are designed for AC230V single-phase systems, while the 4P versions support AC400V three-phase applications, covering many common low-voltage power distribution requirements.

Transfer Time for Backup Power

Fast switching helps reduce interruptions when transferring between power sources. Applications involving communication equipment, automation systems, monitoring devices, or other critical electrical loads often benefit from shorter transfer times. Users should compare transfer specifications when evaluating ATS products.

PROJOY Electric Automatic Transfer Switch completes source transfer in ≤50ms, providing fast response for backup power switching while maintaining stable operation during power recovery.

DIN-Rail Installation and Service Life

Installation method and mechanical durability influence long-term maintenance costs. DIN-rail mounting simplifies installation, while service life specifications provide an indication of expected product reliability over repeated switching operations.

PROJOY Electric ATS features standard DIN-rail installation, a mechanical life of at least 8,000 operations, and an electrical life of at least 1,500 operations, supporting dependable performance throughout extended service periods.

Applications of Automatic Transfer Switch and Changeover Switch

An automatic transfer switch, also known as an automatic changeover switch in some markets, is widely used in backup power systems where loads need to switch between normal power and backup power automatically.

Residential Backup Power Systems

In residential power systems, an automatic transfer switch can be installed in distribution panels to switch household loads between utility power and backup power sources, such as generators or home energy storage systems. This helps keep essential loads powered during unexpected utility outages.

Generator Backup Power Systems

An automatic transfer switch for generator applications is used to transfer loads between grid power and generator power when the main supply fails. It is commonly used in residential buildings, commercial facilities, and small industrial backup power systems that require reliable power transfer during outages.

Solar Energy and Energy Storage Systems

In hybrid solar and energy storage systems, an automatic transfer switch can work with inverters and battery storage systems. When properly configured, the ATS transfers loads between grid power and the backup output from the inverter or energy storage system, helping improve power reliability in renewable energy applications.

Automatic Transfer Switch FAQs

What is ATS in electrical power systems?

ATS stands for Automatic Transfer Switch. It is an electrical device used to automatically switch the load between a normal power source and a backup power source when the main power fails or becomes abnormal.

What does an automatic transfer switch do?

An automatic transfer switch continuously monitors the primary power source. When a power outage or abnormal voltage is detected, it transfers the electrical load to the backup source. After the normal power supply returns and stabilizes, the ATS automatically transfers the load back to the main source.

How to wire a dual power automatic transfer switch for solar and main power?

In a typical dual power installation, the utility power and backup power are connected to the two input terminals of the ATS, while the electrical load is connected to the output terminal. For solar systems, the backup input should normally come from the solar inverter or energy storage output rather than directly from photovoltaic panels.

Can an automatic transfer switch be wired from the top or bottom?

The wiring direction depends on the product design and terminal identification. Installers should always follow the wiring diagram and installation instructions provided with the specific ATS model to ensure safe and correct installation.

What are the key features of PROJOY automatic transfer switch?

PROJOY Electric Automatic Transfer Switch is designed for AC 50/60Hz systems with rated currents from 6A to 63A. It supports automatic and manual operation, provides transfer within 50ms, offers both 2P and 4P configurations, and features compact DIN-rail installation for convenient installation and maintenance.

What is the difference between manual and automatic operation in an ATS?

Automatic mode performs continuous monitoring and switches power sources automatically whenever necessary. Manual mode allows operators to perform testing, maintenance, inspection, or troubleshooting without relying on automatic control.

Is an automatic transfer switch the same as a UPS?

No. An automatic transfer switch and an Uninterruptible Power Supply (UPS) perform different functions. An ATS transfers electrical loads between two power sources, while a UPS temporarily supplies battery power during an outage to bridge the gap before backup power becomes available.