| 摘要 |
<p>PURPOSE:To prevent a starting resistor from overheating or burning by breaking a main circuit when the integrated value of a current of the main circuit becomes the set value or higher. CONSTITUTION:When a feed cam command to cam contactors 5A-5E of a starting resistor 4 is delivered, a reset command is output from a setter/resetter circuit 11, and when the cam command is stopped, the reset command is output. An integrator 12 integrates the current of a main circuit detected by a DC current transformer 6 until the reset command is applied from when a set command is applied. A comparator 13 turns OFF the operating coil 2c of a breaker 2 when the output of the integrator 13 becomes a set value 15 or higher. Thus, it can prevent the resistor from overheating, deforming or burning.</p> |
