Why should a series diode be connected between a solar panel and a storage battery that is being charged by the panel?
The correct answer is B: To prevent discharge of the battery through the panel during times of low or no illumination. Why a series diode should be connected between a solar panel and a storage battery being charged by the panel is to prevent discharge of the battery through the panel during times of low or no illumination. Without the diode, the battery would discharge through the panel when the panel voltage is lower than battery voltage. For amateur radio operators, this protects the battery. Understanding this helps when using solar panels.
Exam Tip
Series diode purpose = prevent battery discharge through panel. Think 'S'eries 'D'iode = 'S'tops 'D'ischarge. Prevents battery from discharging through panel when panel voltage is lower than battery voltage. Not voltage regulation, not current limiting, not voltage protection - just discharge prevention.
Memory Aid
"Series diode purpose = prevent battery discharge through panel. Think 'S'eries 'D'iode = 'S'tops 'D'ischarge. Prevents battery from discharging through panel when panel voltage is lower than battery voltage. Essential for solar charging."
Real-World Application
You connect a solar panel to charge a battery. Without a series diode, when the sun goes down and panel voltage drops below battery voltage, the battery would discharge through the panel. A series diode blocks this reverse current, preventing battery discharge. This is essential for solar charging systems.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Series diode doesn't prevent overload by regulating voltage - diodes don't regulate voltage, they just block reverse current. Voltage regulation isn't the purpose.
Option C: Incorrect. Series diode doesn't limit current to a safe value - diodes have minimal voltage drop, they don't limit current. Current limiting isn't the purpose.
Option D: Incorrect. Series diode doesn't prevent damage from excessive voltage - diodes don't limit voltage, they just block reverse current. Voltage protection isn't the purpose.
题目解析
The correct answer is B: To prevent discharge of the battery through the panel during times of low or no illumination. Why a series diode should be connected between a solar panel and a storage battery being charged by the panel is to prevent discharge of the battery through the panel during times of low or no illumination. Without the diode, the battery would discharge through the panel when the panel voltage is lower than battery voltage. For amateur radio operators, this protects the battery. Understanding this helps when using solar panels.
考试技巧
Series diode purpose = prevent battery discharge through panel. Think 'S'eries 'D'iode = 'S'tops 'D'ischarge. Prevents battery from discharging through panel when panel voltage is lower than battery voltage. Not voltage regulation, not current limiting, not voltage protection - just discharge prevention.
记忆口诀
Series diode purpose = prevent battery discharge through panel. Think 'S'eries 'D'iode = 'S'tops 'D'ischarge. Prevents battery from discharging through panel when panel voltage is lower than battery voltage. Essential for solar charging.
实际应用示例
You connect a solar panel to charge a battery. Without a series diode, when the sun goes down and panel voltage drops below battery voltage, the battery would discharge through the panel. A series diode blocks this reverse current, preventing battery discharge. This is essential for solar charging systems.
错误选项分析
Option A: Incorrect. Series diode doesn't prevent overload by regulating voltage - diodes don't regulate voltage, they just block reverse current. Voltage regulation isn't the purpose. Option C: Incorrect. Series diode doesn't limit current to a safe value - diodes have minimal voltage drop, they don't limit current. Current limiting isn't the purpose. Option D: Incorrect. Series diode doesn't prevent damage from excessive voltage - diodes don't limit voltage, they just block reverse current. Voltage protection isn't the purpose.
知识点
Series diode, Solar panel, Battery discharge prevention, Solar charging
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.