How to discharge the capacitor

At the initial power-on, capacitor C1 is charged through 10K resistor R1, and the C1 potential rises slowly from low level to Vcc and stabilizes.

When the power is off, the potential of C1 is close to Vcc, and it is discharged to the Vcc power supply terminal of the IC through two paths; one way is discharged through R1, and one way is quickly discharged through the diode. If there is no D1, C1 can only pass the 10K resistor to the Vcc power supply of the IC. The end is slowly discharged, so there is D1, and the discharge speed is much faster than the charging speed.

Yes, because of the action of the diode, when the power supply is energized, the diode is reverse biased, which is equivalent to disconnection. The power supply charges the capacitor through the resistor. The charging time is related to the capacitor capacity and the resistance. When the power supply is cut off, the power supply voltage can be considered as 0, that is, VCC is shorted to ground, the capacitor passes through the diode, and the resistor discharges. Because the resistance of the diode conductor is small, the discharge time is short. .

When the capacitor is energized, the capacitor is interrupted. The capacitor stores a certain amount of voltage. When there are other loads or components in the circuit, it will discharge slowly. It can also be quickly discharged by short-circuiting with a small resistor or a wire (low voltage).

What is the principle of capacitance? How to wire?

The capacitor is composed of an insulating material (medium) sandwiched between two metal plate electrodes. When a certain voltage is applied to the two electrodes, an electric field is generated between the electrodes of the two metal plates. Under the action of the electric field, the electrons of the insulating material (medium) of the intermediate clip are pulled close to the positive electrode plate to form a long-lasting The electric field, this process is to charge the capacitor; after the voltage applied to the two electrodes disappears, the electron is subjected to the dual action of the nucleus and the electric field force, there will be a tendency to return to the original position, when the external circuit is connected, the electron is included Under the action of electric field force, return to the other electrode plate through the external circuit, this process is called discharge.

Capacitors can be left as needed. In general, each plate only leads one line, so the general capacitance is two feet.

The 3-pin or 4-pin capacitor you are talking about is generally a double capacitor (two capacitors together, the internals of the 3-pin are connected in series, and the two legs are independent). The upper capacity is generally 2×000μF.

When the capacitor is energized, the capacitor is interrupted. The capacitor stores a certain amount of voltage. When there are other loads or components in the circuit, it will discharge slowly. It can also be quickly discharged by short-circuiting with a small resistor or a wire (low voltage).

When the capacitor is to be discharged, the two poles of the capacitor respectively have a certain amount of charge, and the outside and the capacitor form a closed loop (the power is not included in the general closed loop). In order to force the electrostatic balance to form an electric field in the closed loop, the electric field continuously pushes the capacitor one pole. The excess electrons (negative charge) form a current close to the positive pole of the capacitor, which neutralizes the charge at both ends of the capacitor. When the neutralization is completed, the electric field of the capacitor bipolar disappears, but in the ideal case, in reality, there is always a resistor in the closed loop, so the capacitor amount of charge at both ends is exponentially neutral and tends to zero, but not zero.

When the capacitor is energized, the capacitor is interrupted. The capacitor stores a certain amount of voltage. When there are other loads or components in the circuit, it will discharge slowly. It can also be quickly discharged by short-circuiting with a small resistor or a wire (low voltage).

Chasing

To discharge with metal tools short circuit capacitance can be two feet, if it is a large capacity capacitance can use cement resistance or light bulb to discharge it. High voltage large capacity electrolytic capacitor only need to discharge cut off the power supply, with the plug of the electric soldering iron positive pole and negative pole touch, on the line. Note that if the capacitor voltage and UF is too big positive and negative pole collision will have a very loud sound, it is best to get a lamp or tungsten wire what discharge, so as to be safe.

For small capacitors, direct short-circuit discharge will work. If high-voltage bulk capacitors can only be slowly discharged with resistors, or discharge with 100w incandescent lamps and electric furnace wires, it is also possible in water (but not recommended, if the energy is too large, it will make water Explosion), remember, you must not directly short-circuit the discharge, otherwise the instantaneous energy is infinite, the spark is quite dazzling, the sound is as big as the shells, huh, huh, not to scare you, I tried, will scare people, still Life is dangerous.

Connect a power supply board with a switch. First insert the capacitor into the hole of the board, and turn the switch "on" and "off". The premise is that this capacitor can pass 220VAC, otherwise it will explode.

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