In what scenario is a default SCCR assigned to panelboards and switchboards?

A default Short-Circuit Current Rating (SCCR) is specifically assigned to panelboards and switchboards when short-circuit testing is deemed unnecessary according to the applicable standards. This scenario typically occurs in manufacturing situations where the equipment design is straightforward enough that detailed short-circuit testing can be bypassed. In such cases, standards may allow a default SCCR to be assigned based on standard configurations and components used, ensuring that the equipment still meets minimum safety and performance requirements without necessitating extensive testing.

It's important to understand that while other factors may influence SCCR assignments, the context of deeming short-circuit testing unnecessary is key to establishing the default rating. This is particularly relevant in the electrical industry, where meeting safety and operational standards is crucial, yet efficiency in certification processes can sometimes lead to certain exemptions based on product design familiarity.