What is NOT required to be marked on a controller for air-conditioning and refrigerating equipment?

In the context of air-conditioning and refrigerating equipment, controllers serve specific functions and are subject to various regulations regarding the markings that must be included for safety and effectiveness. The correct answer indicates a marking that is not typically required.

The minimum conductor size is not usually marked directly on the controller. This requirement is often specified in the installation instructions or related documentation, but it is not a standard marking found on the controller itself. Instead, it is expected that installers will reference local codes and standards, as well as manufacturer guidelines, to determine the appropriate conductor size necessary for safe operation.

On the other hand, markings such as the maximum power output, manufacturer details, and operating temperature range are vital for safety, compliance, and proper functioning. Maximum power output allows for safe electrical installations, ensuring that the equipment is not overloaded. Manufacturer details provide traceability and accountability, which can be essential for maintenance, repairs, and warranty purposes. Operating temperature range is crucial for ensuring that the equipment operates efficiently within specified limits, preventing failure and potentially hazardous conditions.

In summary, the omission of minimum conductor size marking on the controller itself reflects industry practices wherein this detail is relegated to documentation rather than direct labeling on the device, focusing on essential safety and operational information instead