| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent an excessive voltage from being applied to a load system due to an excessive voltage of a power source system when power source systems are selectively used. SOLUTION: A source voltage detection part 4 detects and measures the source voltages of a built-in DC power source system 1 and an external DC power source system 2. After the power source is turned ON, a sequence control part 5 selects the external DC power source system 2 by a power source switching part 3, checks the source voltage of this external DC power source system 2, and executes a sequence for normal subsequent operation when the source voltage is lower than a specific voltage. When the source voltage of the external DC power source system 2 exceeds the specific voltage, the sequence control part 5 selects the built-in DC power source system 1 by the power source switching part 3, checks the source voltage of this built-in DC power source system 1, and performs a sequence for normal subsequent operation when the source voltage is lower than the specific voltage. When the source voltage of the built-in power source system 1 exceeds the specific voltage, the process is repeated.</p> |
