Ham Amateur Radio Technician Practice Exam

What is the purpose of a power supply interlock?

1. To initiate power saving mode

2. To ensure that dangerous voltages are removed if the cabinet is opened

3. To enhance energy efficiency

4. To activate backup power systems

The correct answer is: To ensure that dangerous voltages are removed if the cabinet is opened

A power supply interlock is designed primarily to enhance safety by ensuring that dangerous voltages are removed when the equipment's cabinet is accessed or opened. This is a critical safety mechanism, particularly in high-voltage environments, as it helps prevent accidental electric shock or injury to personnel who may be performing maintenance or inspections inside the equipment. When the interlock is activated (for example, when the cabinet is opened), it disconnects the power supply, effectively cutting off the hazardous voltages that could pose a risk to an individual's safety. This design feature is essential in all sorts of electrical and electronic equipment, especially in amateur radio setups that may involve high voltage or current levels. While power saving modes and energy efficiency are important considerations in many electronic devices, they are not the primary function of a power supply interlock. Similarly, activating backup power systems is unrelated to the interlock’s primary focus on safety in instances where access to the device’s internal components is necessary. Thus, the interlock's sole purpose is to ensure that sufficient safety measures are in place when handling potentially dangerous equipment.