Primary switching architecture

Static Transfer Switches (STSs) are central components in data center power system

configurations. The typical system design incorporates two separate uninterruptible power

supplies (UPSs), Source 1 and Source 2 feeding the preferred and alternate sources of the STS.

These devices are the bridge between the power sources UPSs and the power

distribution units (PDUs) where a transformer is needed to typically switch the 480V

side (primary) to the 208V side (secondary). The primary side switching (480V) is the most common

and cost effective architecture to the customer in terms of smaller footprint and lower costs because

only one transformer is needed. The alternative architecture would be to switch the secondary

which would require each source to have its own fully rated transformer (208V).

Data center: Mission critical facilities used to house computer, network, data storage,

telecommunications, and other vital systems that require constant power with no interruptions.

Hospitals: Health care institutions that require constant power with no interruptions to data and

records management.