Short Circuit Current Rating - SCCR
Assembly short-circuit current rating, SCCR
Definition: SCCR on components and assemblies represent the maximum level of short-circuit current that a component or assembly can withstand. This rating is used to determine compliance with NEC 110.10. “SCCR” labeling is required on all panels and assemblies.
Control Concepts’ FUSION digital power controllers that are rated less than 500 amps have been tested up to 100 kA with internal protection of the current limit and over current trip defeated. This rating only pertains when the volume of the enclosure is 150% of the controller volume, the enclosure has two latches on the cover and the controller is protected with Class T or High Speed J fast acting fuses.
Other Control Concepts controllers with UL listing have a default SCCR rating of 5 kA. No SCCR testing has been performed on these SCR products.
Further information can be obtained from the following:
Underwriters Laboratories: UL508A supplement SB
2005 National Electrical Code (NEC) [Article 409.110]
Littelfuse: http://www.littelfuse.com/electrical/SCCR-center.html
Bussmann: http://marketing.bussmann.com/library/advancedsccr.pdf
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