Panel boards equipped with snap switches rated at 30 Amps or less must have over-current protection not exceeding what rating?

Panel boards equipped with snap switches rated at 30 Amps or less must have over-current protection that does not exceed 200 Amps. This requirement is derived from the National Electrical Code (NEC) and is crucial for ensuring safety and preventing equipment damage.

The rationale behind this limit is to protect the smaller rated snap switches from currents that could exceed their ratings, which could lead to overheating or failure. While the panel board itself may handle higher currents, the protection mechanism needs to match the weakest point in the system, which, in this case, are the snap switches rated at 30 Amps or less.

Having an over-current protection setting higher than 200 Amps could allow excessive current to flow through the snap switches, posing serious safety risks and potentially causing fires or equipment malfunction. Therefore, setting the over-current protection at a maximum of 200 Amps appropriately aligns with the requirement for maintaining safe operational limits for snap switches in the panel boards.