| 摘要 |
<p>The demagnetising circuit, is used with an electromagnet, it has a capacitor (18) which is connected in series with a resistor (17) across the coil (13) of the electromagnet assembly. The RC circuit causes damped oscillations when the switch (12) is opened and ensures that the magnetic field returns to its initial zero value; it overcomes the effects of hysteresis in the magnet. Removing the residual field in this way prevents the armature remaining attracted to the core.</p> |
