What should the power transformer for an alarm panel never be plugged into?

The power transformer for an alarm panel should never be plugged into a switched outlet. This is because a switched outlet can be turned off, which would deactivate the alarm panel without the knowledge of the user. Alarm systems rely on constant power to function reliably and consistently monitor for intrusions. If the power is inadvertently cut off by switching off the outlet, it can lead to a lapse in the system's monitoring capabilities, compromising security.

Using an outlet designated for specific purposes or an outlet protected by a GFCI (Ground Fault Circuit Interrupter) breaker may be acceptable depending on the environment and the specific regulations or recommendations for alarm installations. However, the fundamental issue with switched outlets is that they introduce the risk of unintentional deactivation which could leave a premises vulnerable to unauthorized entry.

Therefore, the correct understanding involves recognizing the inherent risks associated with switching the power off to an alarm system and ensuring that the transformer is connected to a dedicated, always-on source to maintain uninterrupted operation.