What is required for primary power supplies that use Class 2 or Class 3 plug-in transformers?

For primary power supplies that utilize Class 2 or Class 3 plug-in transformers, the requirement for mechanical security is crucial. This means that the power supply must be securely fastened or anchored to prevent accidental disconnections or movements that could lead to hazards. Mechanical securing is necessary to ensure the integrity of the electrical connection and to minimize the risk of damage to the transformer or the system it powers.

Class 2 and Class 3 transformers are designed with certain limitations to ensure safety, both in terms of the current they can carry and the potential for fault conditions. By requiring mechanical security, regulations help to maintain a stable and safe environment where the transformers operate within their designated parameters.

In contrast, the other answer options do not reflect the critical safety and operational requirements as defined for these types of transformers. While mobility, direct connections to outlets, and environmental conditions are important considerations, they do not specifically address the need for securely mounting the device to ensure safety and functionality in everyday use.