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What is a "fully rated" system versus a "series rated" system?

Issue:
Determining the short-circuit current rating (SCCR) of a system

Product Line:
Panelboards, switchboards, molded case breakers, fusible switches

Environment:
All Square D panelboards, switchboards, and load centers

Resolution:
A "fully rated" system is one where each over current device is rated for the available fault current present at the line side terminals of the device.

In contrast, a "series rated" system may contain components whose labels reflect a short-circuit rating lower than the actual available fault current. This application is allowed where the manufacturer has documentation and additional equipment labeling referencing actual test results where two or more over current devices were wired together in a test cell and subjected to a set fault current on the load side of the last breaker, demonstrating the circuit is successfully protected and all breakers in the circuit can be reset, retested, and operate.

For additional details, see product data bulletin 2700DB9901.