Backup battery 12V 7A for Systems Battery Brand Product and Access control Backup Power Supply

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What is in a power supply?

A power supply is an electrical device that supplies electric power to an electrical load. ... All power supplies have a power input connection, which receives energy in the form of electric current from a source, and one or more power output connections that deliver current to the load.

Why do we need power supply?

One purpose of a power supply is to convert AC to DC so the computer has proper power to run its components. ... Another purpose of a power supply is to distribute proper DC voltage to each component. Several cables with connectors come out of the power supply.