What is an uninterruptible power supply?

Uninterruptible power supplies, also known as UPS, are used to provide backup power and protect electrical apparatus from power outages. They can also regulate and protect the attached equipment from abnormal voltages.

Some UPS systems can also regulate and protect attached apparatus from abnormal voltages. UPS systems have two main functions; to provide battery backup power and to protect apparatus from power surges and line noise interference.