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

Determining the SCCR of a system

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

All Square D panelboards, switchboards, and load centers

A “fully rated” system is one where each overcurrent device is rated for the available fault current present at the terminal of the device.  In contrast a “series rated” system may contain components whose labels reflect a short circuit ratings 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 overcurrent devices were wired together in a test cell and subjected to a set fault current on the load side of the last breaker, and the circuit is successfully protected and all breakers in the circuit can be reset, retested, and operate.  See product data bulletin 2700DB9901.
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