One-use one-standby power supply program means that there is only one main power supply in the system, and the standby power supply is usually in standby mode, and will automatically switch to the standby power supply only when the main power supply fails or the power goes out. The power supply mode of this program for a single power supply, and can only be switched from the main power supply to the standby power supply, can not realize the two-way switching. It is generally used for relatively low power requirements, a short period of time when the power supply is suspended, such as household appliances.
The dual power supply refers to the system has two independent power supplies, under normal circumstances, the two power supplies can work at the same time, each as a backup. When one of the power supply fails or needs maintenance, the system can automatically switch the load to the other normally operating power supply, realizing a two-way switch. The power supply of this scheme is double power supply and can realize two-way switching. It is generally used for occasions with high power requirements, long outage times, and high reliability requirements, such as medical equipment and computer data centers.
In short, a standby power supply program and dual power supply in the power supply mode and power supply switching mode is significantly different, should be based on the actual needs of the appropriate power supply program.