Issue:
Short circuit current rating (SCCR) for class 9422 type T disconnect switches.
Product Line:
Operating Mechanisms and Disconnect Switches
Environment:
9422 Disconnect Switches
Resolution:
When mounted in a correctly sized enclosure per UL requirements, class 9422 type T switch assemblies are suitable for use with short circuit current ratings (SCCR) as follows:
The stand-alone SCCR for class 9422 type T non-fused disconnect switches is 10kA @ 600Vac.
When a class 9422 type T non-fused disconnect is protected by external fuses, it carries an SCCR equivalent to the interrupting rating of the fuses up to a maximum of 200kA @ 600Vac.
When a class 9422 type T non-fused disconnects is protected by a properly rated PowerPact H or J-frame molded case circuit breaker, the disconnect carries an SCCR equivalent to the interrupting rating of the breaker up to a maximum of 65kA @ 240Vac, 35kA @ 480Vac, or 25kA @ 600Vac.
Class 9422 type T fused disconnect switches carry an SCCR equivalent to the interrupting rating of the installed fuses up to a maximum of 200kA @ 600Vac.
Refer to these instruction sheets for these disconnect switches for further details:
{insert links to all instruction sheets}
Short circuit current rating (SCCR) for class 9422 type T disconnect switches.
Product Line:
Operating Mechanisms and Disconnect Switches
Environment:
9422 Disconnect Switches
Resolution:
When mounted in a correctly sized enclosure per UL requirements, class 9422 type T switch assemblies are suitable for use with short circuit current ratings (SCCR) as follows:
The stand-alone SCCR for class 9422 type T non-fused disconnect switches is 10kA @ 600Vac.
When a class 9422 type T non-fused disconnect is protected by external fuses, it carries an SCCR equivalent to the interrupting rating of the fuses up to a maximum of 200kA @ 600Vac.
When a class 9422 type T non-fused disconnects is protected by a properly rated PowerPact H or J-frame molded case circuit breaker, the disconnect carries an SCCR equivalent to the interrupting rating of the breaker up to a maximum of 65kA @ 240Vac, 35kA @ 480Vac, or 25kA @ 600Vac.
Class 9422 type T fused disconnect switches carry an SCCR equivalent to the interrupting rating of the installed fuses up to a maximum of 200kA @ 600Vac.
Refer to these instruction sheets for these disconnect switches for further details:
{insert links to all instruction sheets}