reverse 1999 circuit puzzle

The following are a few types of circuits to prevent reverse power supply: 1. ** Diode-proof reverse connection circuit **: A single circuit is connected in series to the power supply input end. By using the one-way conductivity of the circuit, it can conduct in the forward direction and cut off in the reverse direction. When the power supply was reversed, the LED would not conduct, thus avoiding reverse power supply. However, during normal operation, a voltage drop of 0.7V will occur on the LED, which is not suitable for circuits with strict requirements on the supply voltage. 2. ** Fuse + Parallel Diode **: The principle is also based on the one-way conductivity of the Diode. When the power supply is connected normally, the LED does not work, and the current flows into the circuit through the fuse. After the power supply is connected in reverse, the LED is instantly turned on, causing the positive and negative poles of the power supply to be short-circuited. The short-circuit current generated by the short-circuit fuses the fuse, achieving the effect of reverse connection protection. However, the fuse selection must be compatible with the circuit characteristics. 3. ** Full-bridge Rectifiers Anti-reverse Connection Circuit **: No matter what the input power is, the output is always fixed, so it can work regardless of the positive and negative connection circuit. However, when it works, the full-bridge rectify will produce a voltage drop of about 1.5V. 4. ** Low internal resistance of the anti-reverse connection circuit of the upheaval protector **: When the power supply is normally connected, the upheaval protector is turned on. After the power supply is reversed, the upheaval protector is turned off to achieve reverse connection protection. Due to factors such as the improvement of the process technology, the internal resistance of the semiconductor was extremely small, and the impact on the voltage drop and power consumption of the circuit was minimal. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

The following is a basic method to draw a positive and negative ladder diagram and circuit diagram: ** 1. Confirm control requirements and I/O allocation ** 1. ** Clear control requirements ** - Usually, the forward and reverse control required the motor to rotate forward, reverse, and stop through buttons, and it had to be interlocked with forward and reverse (to prevent short circuits caused by forward and reverse rotation at the same time). It might also require thermal relay for overload protection and other functions. 2. **I/O allocation confirmed ** - ** Inputs **: For example, the start button for forward rotation, the start button for reverse rotation, the stop button, and the overload protection signal of the thermal relay are all used as input signals. These input signals should be distributed to the corresponding input terminal of the PC. For example, in the case of the Mitsui PC, it may be X000, X001, etc., and in the case of the siemen PC, it may be I0.0, I0.1, etc. - ** Outputs **: Forward Contactor Coils and Reverse Contactor Coils are used as the output devices. They should be connected to the corresponding output terminal of the PC, such as Y000 and Y001 of the Mitsubishi-based PC, Q0.0 and Q0.1 of the SIEMEN-based PC, etc. ** 2. Draw the circuit diagram (Take the three-phase induction motor as an example)** 1. ** Main circuit part ** - The three-phase power supply was connected to the fuse (for short-circuit protection) and then connected to the main contact of the contactors. For forward rotation, when the main contact of the forward rotation contactors (KM1) is closed, the three-phase power supply is connected to the motor according to the normal phase sequence, and the motor is rotated forward. For reversal, when the main contact of the reversal contactors (KM2) is closed, the phase sequence of two phases of the three-phase power supply is reversed and then connected to the motor, and the motor is reversed. At the same time, the thermal relay (FT) should be connected to the circuit to detect the current of the motor and automatically cut off the circuit when overloaded. 2. ** Control Circuit ** - ** Forward control circuit **: Lead out from one end of the power supply, first connect the stop button (normally closed), then connect the forward start button (normally open) and the auxiliary normally open contact (for self-locking) of the forward rotating contactors (KM1) in series, then connect the auxiliary normally closed contact (for interlocked) of the reversing contactors (KM2) in series, and finally connect to the coil of the forward rotating contactors (KM1). The other end of the coil returns to the other end of the power supply. - ** Reverse control circuit **: It is also led out from one end of the power supply. First, connect the stop button (normally closed), then connect the reverse start button (normally open) and the auxiliary normally open contact of the reversing contactors (KM2) in series (for self-locking), then connect the auxiliary normally closed contact of the forward rotating contactors (KM1) in series (for interlocked), and finally connect to the coil of the reversing contactors (KM2). The other end of the coil returns to the other end of the power supply. - ** Overload protection part **: The normally closed contact of the thermal relay (FT) is connected in series to the common part of the control circuit (i.e. behind the stop button). When the motor is overloaded, the thermal relay will act, and the normally closed contact will be disconnected, cutting off the entire control circuit. ** 3. Draw the ladder diagram (Take the SIEMens's PL as an example)** 1. ** Forward Rotation Control Logics ** - I0.0 is used as the input signal of the forward start button, I0.1 is used as the input signal of the stop button, I0.2 is used as the input signal of the reverse start button (all are normally open contact input), Q0.0 is used as the output signal of the forward contact coil, and Q0.1 is used as the output signal of the reverse contact coil. - When I0.0 is pressed (the normally open contact is closed) and I0.1 is not pressed (the normally closed contact is closed) and Q0.1 is not energized (the normally closed contact is closed), Q0.0 is energized and self-locked (the normally open contact of Q0.0 is closed to maintain its energized state). - In the ladder diagram, it is represented as: the normally closed contacts of I0.0 and I0.1, the normally closed contact of Q0.1 are connected in series to the coil of Q0.0, and the normally open contact of Q0.0 is connected in parallel with I0.0 to achieve self-locking. 2. ** Reverse control logic ** - When I0.2 is pressed (the normally open contact is closed) and I0.1 is not pressed (the normally closed contact is closed) and Q0.0 is not energized (the normally closed contact is closed), Q0.1 is energized and self-locking. - In the ladder diagram, it is represented as: the normally closed contacts of I0.2 and I0.1, the normally closed contact of Q0.0 are connected in series to the coil of Q0.1, and the normally open contact of Q0.1 is connected in parallel with I0.2 to achieve self-locking. The specific instructions, component representation, and programming rules of different brands of PDLCs (e.g., Samsung, SIEMENS, etc.) may differ, but the basic control logic and design ideas are similar. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

This isn't related to the novel, but I can briefly tell you the key points of the positive and negative circuit connection of the three-phase induction motor. Three-phase induction motor to achieve positive and negative transfer line, mainly by changing the phase sequence of the motor three-phase power supply to achieve. Generally, two contactors would be used. The three-phase power supply of one of the contactors would be connected in the normal order, such as A-B- C. The three-phase power supply of the other contactors would be changed to C-B- A. In terms of the control circuit, it should be interlocked to prevent the two contactors from short-circuiting at the same time. However, this was just a simple introduction. The actual connection must be strictly in accordance with the electrical safety regulations. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

The working principle of the three-phase induction motor reverse connection control circuit is as follows: 1. Reverse braking was completed with the help of the speed relay SD. There was a heavy object in the speed relay mechanically connected to the motor shaft. 2. After pressing the start button, the motor of the SSB1 rotated to a certain speed. Due to the inertia, the weight pressed the speed relay micro-switch to send a signal, and the SD contact was connected. 3. When the stop button SSB0 is pressed, the KM1 loses power, and the motor enters the free parking state instantly after being disconnected from the power supply; after the normally closed contact of the KM1 recovers, the KM2 is energized, and the motor enters the braking state after being connected with the reverse power supply; when the speed of the motor drops and is lower than the speed at which the speed relay contacts are pressed together, the speed relay micro switch is disconnected, and the motor enters the free parking state again until it completely stops. 4. For KM1 and KM2, AC contactors with mechanical interlocks shall be selected, and their normally closed contacts shall be set with electrical interlocks to ensure safety. 5. Circuit breakers QF1 and QF2 are used for short-circuit protection, and thermal relay KH is used for long-term overload protection of the motor. 6. The resistance R was used to adjust the brake strength. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

In an amplifier circuit, a circuit with feedback was called a closed-loop circuit. The feedback amplifier circuit had a feedback path from the output to the input. This feedback circuit was in a closed-loop state, so the feedback amplifier circuit was a closed-loop circuit. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

A one-way circuit had only one line and one neutral line. The current flowed from the line to the neutral line. For example, many electrical appliances in our home use a one-way circuit, such as lights and televisions. It is relatively simple, and the voltage is usually 220V. In a three-phase circuit, there were three live wires and sometimes a neutral wire. The voltage between the three wires was 380V. This kind of circuit was commonly used in the industry. For example, some large-scale electric machines used three-phase circuits. The three-phase circuit could provide more power than the one-way circuit, and it was more efficient. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

One-way circuits and three-phase circuits had their own characteristics and were suitable for different scenarios. It was not easy to determine which one was better. From the perspective of transmission cost and non-metallic consumption, under the same transmission power, distance, voltage, and line loss, three-phase transmission lines can save a lot of transmission costs and non-metallic metals. The amount of copper used is about 3/4 of that of single-phase transmission lines. In terms of generators, three-phase alternators were smaller, lighter, and cheaper than single-phase alternators of the same capacity. A three-phase transformer was not only more economical than a single-phase transformer, but it also had two types of output voltage. It could be connected to either a three-phase load or a single-phase load. For the motor, the three-phase motor was simpler in structure than the single-phase motor of the same capacity. It was reliable, cheap, had good performance, stable operation, and high efficiency. Three-phase power sources were easier to generate rotating magnetic fields and were suitable for powering three-phase electric machines, while single-phase circuits were relatively inferior in this regard. However, in daily life scenarios, such as household electricity, a single-phase circuit could meet the electricity needs of electric appliances such as lights, computers, electric kettles, fridges, and 1P air conditioning. Because the power of these appliances was relatively small, 220V single-phase alternating current could be used. In the industry, due to the large power of the equipment, the need for a stable rotating magnetic field, and for economic considerations, most of them used three-phase electricity. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

Well, it's possible that 'The Circuit' is based on true events to some extent, but it could also be a completely fictional creation designed to engage and captivate the audience.

It's hard to say for sure whether the circuit is fiction or nonfiction without more details. If it's described with scientific accuracy and relates to real-world electronics, it's nonfiction. If it has elements of fantasy or imagination, it might be fiction.