Under which condition would a switchboard likely sustain extensive damage?

The correct condition that would likely lead to extensive damage to a switchboard is when the fault current exceeds the rated Short-Circuit Current Rating (SCCR) of any section. The SCCR of a switchboard is a critical rating that indicates the maximum amount of fault current the equipment can withstand without sustaining damage during a short circuit event. If the actual fault current that flows through the switchboard during a fault condition exceeds this rating, it means the components within the switchboard may not be able to safely manage or contain the fault. This could lead to catastrophic failures such as component melting, fires, or even explosions due to the immense energy involved. Thus, adhering to and understanding the SCCR is vital for preventing damage and ensuring safe operation of electrical systems.

In contrast, having the SCCR rated higher than the expected fault current does not pose a risk; it signifies that the switchboard is equipped to handle the potential fault without sustaining damage. Installing equipment outdoors may expose it to environmental factors but does not inherently lead to extensive damage unless the equipment is not designed for such conditions. Lastly, having all equipment from the same manufacturer might aid in compatibility and streamline maintenance but does not directly correlate with the ability to withstand fault currents or prevent damage.