Connecting a properly rated zener diode across a power supply load will primarily do what?

When a properly rated zener diode is connected across a power supply load, its primary function is to limit the output DC voltage to a specified level, known as the zener voltage. This voltage regulation occurs because the zener diode allows current to pass when the voltage across it reaches its breakdown voltage, effectively keeping the output voltage stable and preventing it from rising above that level, regardless of variations in the input voltage or load conditions.

This functionality is particularly useful in applications where a consistent voltage is required for other components or circuits downstream. As the current increases and voltage across the zener reaches its rated level, the diode enters breakdown, and additional current flowing through it ensures that any further increase in input voltage does not lead to an increase in the output voltage.

The other options do not accurately reflect the role of a zener diode in this context. The zener does not increase the output voltage; it regulates it. Likewise, while limiting the output voltage might indirectly lead to a more consistent power feature, it does not inherently reduce overall power consumption, which depends on the entire circuit design and load conditions. Thus, the correct answer highlights the key function of voltage regulation provided by the zener diode.