Light, is the origin of all good things. It has illuminated the course of human civilisation, from ignorance to shining wisdom.
We worship the sun and the moon, but also created the miracle of photoelectricity.
Electricity, breaking the bonds of darkness, lighting up our lives. Its existence, so that the world is full of light, so that we are closely linked to share the good.
From the coffee machine in the morning light to the lights at night, modern people enjoy unprecedented efficiency and freedom under the empowerment of electricity. Electricity has become the indispensable heartbeat of modern civilisation.
However, in the face of sudden blackouts or power fluctuations, the stability and continuity of the power system is particularly important. At this point, the role of dual power automatic transfer switch – a key component of modern electrical infrastructure – becomes even more indispensable.
Ⅰ. What is an Automatic Transfer Switch?
Automatic Transfer Switch (ATS) is an electrical device used for automatic switching between two power sources.
ATS is primarily used in emergency power systems, essentially handling the switch between the main power source and the backup power source. When the main power source experiences a sudden failure (such as loss of voltage, overvoltage, undervoltage, frequency deviation, etc.) or a power outage, the ATS automatically switches to the backup power source, allowing the equipment to continue operating normally.
The development of ATS has progressed through several stages:
Initially, contactors were used to establish a dual power conversion system, but this required the collection of power supply operating conditions, the switching status of the two power sources, and then the design of the control conversion method. Later, after actual operation, it was found that the wiring was basically the same each time, and there was too much repetitive wiring. Therefore, people decided to extract the common part, installed in a whole board, forming an independent module, so that in the use of only simple wiring can be.
Thus, the automatic transfer switch was born.
Ⅱ. How Does an Automatic Transfer Switch Work?
When the main power source is functioning normally and the function switch is set to automatic mode, the backup circuit breaker is closed, and the main circuit breaker is open, ensuring that the main power source supplies the load.
The microcomputer control circuit monitors the voltage of both power sources and makes judgments based on the detection results. If any phase of the main power source experiences a fault, the ATS will switch the power supply from the main power source to the backup power source. Once the main power source returns to normal, the system will automatically switch back to the main power source to continue supplying power.
If a fault is detected in the backup power source, an alarm will sound, alerting the user to inspect and repair the backup power source as soon as possible, ensuring that the main power source can continue to supply power normally.
Ⅲ. What is the Difference Between ATS and STS?
First, we need to understand what STS is. A Static Transfer Switch (STS) is an automatic static switching device, which functions similarly to an ATS, allowing for uninterrupted circuit switching. However, compared to traditional ATS, the switching speed of STS can reach the millisecond level (≤8ms).
1、Working Principle
An ATS typically relies on motor-driven or electromagnetic mechanisms to perform power switching, whereas an STS uses solid-state electronic components (such as thyristors or IGBTs) to achieve switching.
2、Application Scenarios
ATS is suitable for scenarios where switching speed is not a critical factor, such as in power equipment for data centers in standard commercial and industrial environments. It is primarily used for non-critical load power switching.
On the other hand, STS is ideal for situations requiring extremely high power continuity, such as high-end data centers, communication base stations, medical equipment, and essential industrial control systems. STS can swiftly switch to a backup power source the instant a power failure occurs, ensuring uninterrupted operation of the equipment.
3、Power Range
ATS can be used across a wider power range, from small commercial equipment to large industrial facilities.
STS is generally used in medium to small power applications, especially those requiring high reliability and rapid switching for critical loads.
