Dual power automatic switch is a device controlled by a microprocessor, used for starting and switching between grid power and grid power or grid power and generator power in the power grid system, which can provide continuous power supply. Series dual power supply, when the common power suddenly fails or loses power, it automatically switches to the backup power supply through the dual power switch (the backup power supply can also be supplied by the generator under low load), so that the equipment can still operate normally. The most common ones are elevators, fire protection, surveillance systems, lighting, etc.

A dual power conversion switch appliance (conversion switch) is an appliance that converts one or several load circuits from one power source to another. An appliance consisting of one (or several) switching devices and other necessary electrical components, used to monitor power circuits and automatically switch one or several load circuits from one power source to another. In the electrical industry, it is commonly referred to as "dual power automatic transfer switch" or "dual power switch". The national standard for ATS products is defined as an electrical appliance consisting of one (or several) conversion switch devices and other necessary devices, used to detect power circuits and automatically convert one or more load circuits from one power source to another ATS is suitable for dual power supply of key loads such as fire protection in the construction field, while EPS is suitable for EPS. EPS is mainly aimed at solving the first level load power supply equipment such as emergency lighting, accident lighting, and fire protection facilities, providing an emergency power supply system with independent circuits that complies with fire protection regulations. UPS mainly provides electricity for IT industry equipment, offering pure and uninterrupted backup power. The diesel generator power supply method is suitable for use in conjunction with ATS, EPS, and UPS in power supply locations that require long-term backup power.