Class 2 and Class 3 circuits must be separated from Class 1 conductors by what type of barrier?

Class 2 and Class 3 circuits are designed for low-voltage applications and are subject to specific safety and installation requirements outlined in the National Electrical Code (NEC). These circuits must be separated from Class 1 conductors, which handle higher voltage and power levels, to ensure safety and prevent interference.

A barrier is the appropriate method to provide this required separation. Barriers may include physical partitions or enclosures that restrict the proximity of Class 2 and Class 3 circuits to Class 1 circuits. This separation mitigates the risk of electric shock or fire by preventing unintended contact between the different types of circuits and helps maintain the integrity of the signals in Class 2 and Class 3 installations.

Considering the other options, while insulation can help prevent electric shock, it does not fulfill the requirement for physical separation required by the NEC in this context. Grounding is crucial for electrical safety but does not serve as a physical barrier. Shielding may be used to protect against electromagnetic interference but does not provide the necessary separation required between these classes of circuits. Thus, the use of a barrier is key to adhering to safety standards and regulations.