A capacitor/resistor question

Greetings All, In the book "Electric Motors and Control Techniques" a circuit is illustrated that is for the dynamic braking of a squirrel cage motor. This circuit discharges a capacitor through the field windings to slow the motor. The capacitor is connected across the AC power to the motor in series with a 50k resistor and a diode. I under stand why the diode is there. The resistor must be there to slow the rate at which the cap is charged. Is this done just to limit the current when the cap is charging? When the cap is discharged through the windings it is connected to the windings only and does not discharge through resistor. Thanks, Eric

Reply to
etpm
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You have a grasp on it. A capacitor when discharged will present a low impedance (or resistance)at first and then look more like an open circuit as it charges. The resistor is to prevent a large inrush current when power is first applied. The cap is charged to DC and when released to the coil will brake the rotation. A little more to say but this is the basis of what you asked.

Tom

Reply to
Tom Biasi

Thanks Tom, It's nice to know when I'm thinking about things the right way. Eric

Reply to
etpm

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