Final answer:
Whether Class 2 control circuit wiring is permitted to pass through the line voltage of the enclosure without splices depends on local electrical codes, typically aligned with the NEC. These rules must be consulted to ensure safety and compliance.
Step-by-step explanation:
The statement that when class 2 control circuit wiring enters the wiring enclosure of a piece of equipment, this wiring is permitted to pass through the line voltage of the enclosure if no splices are made in the Class 2 wiring needs to be evaluated based on the local electrical codes which generally follow the guidelines of the National Electrical Code (NEC). However, typically, Class 2 circuits are considered low-voltage and energy-limited, which provides an inherent safety due to low power levels and thus may be permitted to coexist within the same enclosure as higher voltage circuits, provided they are separated and no connections are made between them. To ascertain if this is allowed, one would need to refer to the specific rules set out in the NEC, or other relevant local codes that pertain to the separation of circuits of different classes. It's important that they are installed according to the manufacturer's instructions and local code requirements to prevent electrical interference and ensure safety.