*Question E7D11:
What is the purpose of an inverter connected to a solar panel output?*  

*Correct Answer is  D: Convert the panel’s output from DC to AC*  

### AI Response: (may contain errors)  

The correct answer to the question about the purpose of an inverter connected to a solar panel output is:

**D: Convert the panel’s output from DC to AC.**

### Explanation of the Correct Answer:
- **Inverters** are devices that convert direct current (DC) produced by solar panels into alternating current (AC), which is the form of electricity used by most household appliances and the electrical grid. This conversion is essential for integrating solar power into home systems and the grid.

### Why the Other Choices are Incorrect:
- **A: Reduce AC ripple on the output**  
  - This is incorrect because inverters are designed to produce a stable AC output, but their primary function is not to reduce ripple. Ripple is more relevant in power supply design, where filtering is used to smooth out the output.

- **B: Maintain voltage with varying illumination levels**  
  - While inverters can help manage output voltage, their main role is not to maintain voltage levels. Instead, they convert the DC output to AC. Voltage regulation is typically handled by other components in a solar power system, such as charge controllers.

- **C: Prevent discharge when panel is not illuminated**  
  - This is incorrect because preventing discharge (or reverse current) is usually managed by diodes, specifically blocking diodes, rather than the inverter itself. The inverter's role is focused on conversion rather than discharge prevention.

### Useful Formulas or Rules of Thumb:
- The output voltage of a solar panel can vary based on illumination, but the inverter's job is to ensure that the output remains usable AC power. 

- A common rule of thumb is that the efficiency of a good inverter is typically around 90-95%, meaning that it effectively converts most of the DC power into AC with minimal losses.

In summary, the primary function of an inverter in a solar power system is to convert the DC output from solar panels into AC, making it suitable for use in homes and for feeding into the electrical grid.