Maintenance electrician technician exam question bank 300 questions - Database & Sql Blog Articles

Judgment 1. The magnitude of the coil's self-induced electromotive force is proportional to the rate of change of the current in the coil, independent of the magnitude of the current in the coil.
2. When the capacity of the capacitor and the voltage at both ends are constant, the higher the frequency of the power supply, the smaller the reactive power of the circuit.
3. In the RLC series circuit, the effective value of the total voltage is always greater than the voltage rms value on each component.
4. When the RLC series circuit resonates, the current in the circuit will reach its maximum value.
5. Magnetic circuit Ohm's law applies to a magnetic circuit with only one medium.
6. If the U-phase voltage of the symmetrical three-phase power supply is Uu=100sin(ωt+60) V and the phase sequence is U-V-W, the line voltage is Uuv=173.2sin(ωt+90) when the power supply is star-connected. ) V.
7. When the three-phase load is connected in delta, if the three phase currents are equal, the three line currents must be equal.
8. Single-phase bridge rectifier circuit with capacitive filtering, the average value of the output voltage is independent of the magnitude of the load.
9. In the simple shunt regulator circuit of the silicon voltage regulator, the Zener diode should work in the reverse breakdown state and should be connected in series with the load resistor.
10. When the emitter junction of the transistor is positively biased, the transistor must operate in the amplification region.
11. When drawing the AC channel of the amplifier circuit, the capacitor can be regarded as an open circuit, and the DC power supply can be regarded as a short circuit.
12. The input resistance of the amplifier is the DC equivalent resistance seen from the input of the amplifier.
13. For the NPN type transistor common emitter circuit, when the emitter junction bias voltage Ube is increased, the input resistance also increases.
14. The transistor is a current controlled semiconductor device, and the field effect transistor is a voltage type control semiconductor device.
15. A unipolar device is a semiconductor device that relies solely on a single majority carrier to conduct electricity.
16. The low-frequency transconductance of the FET is an important parameter to describe the effect of the gate voltage on the drain current control. The larger the value, the stronger the control capability of the FET.
17. For a linear amplifying circuit, as the amplitude of the input signal decreases, its voltage amplification factor also decreases.
18. The amplifier circuit introduces negative feedback, which can reduce nonlinear distortion, but cannot eliminate distortion.
19. The negative feedback in the amplifying circuit has an inhibitory effect on the interference, noise and distortion generated in the feedback loop, but has no ability to suppress the interference signal contained in the input signal.
20 The differential amplifier circuit can completely eliminate the zero drift phenomenon under ideal symmetry.
21 When the differential amplifier circuit operates in the linear region, as long as the signal is input from a single-ended terminal, the voltage amplification factor must be half of the amplification factor from the double-ended output, regardless of whether the input terminal is a single-ended input or a double-ended input.
22 The input stage of an integrated op amp typically uses a differential amplifier circuit, which is designed to achieve higher voltage amplification.
23 The internal circuit of the integrated op amp is generally directly coupled, so it can only amplify the DC signal and not amplify the AC signal.
When the integrated op amp is operating, the potential difference between its inverting input and its non-inverting input is always zero.
25 As long as it is an ideal op amp, whether it works in a linear state or in a non-linear state, neither the inverting input nor the non-inverting input request current from the signal source.
26 When the actual operation is open loop, its output is difficult to adjust to zero potential, and can only be adjusted to zero potential when closed loop.
27 The voltage amplifier mainly amplifies the voltage of the signal, while the power amplifier mainly amplifies the power of the signal.
28 Graphical methods are usually used to analyze power amplifiers, and micro-variable equivalent circuits cannot be used.
29 Any power amplifying circuit has the smallest loss of its power amplifier tube when its output power is maximum.
The adjustment tube in the 30 CW78XX series three-terminal integrated voltage regulator must work in the switching state.
31 The output voltage of various three-terminal integrated regulators cannot be adjusted.
32 For greater output current capacity, multiple three-terminal regulators can be used in parallel directly.
33 The output of the three-terminal integrated voltage regulator has positive and negative points and should be used correctly as needed.
After a logical function expression of 35 people has been simplified, its minimal form must be unique.
36 TTL NAND gate inputs can resolve any resistor value without affecting its output level.
37 The output of the normal TTL NAND gate cannot be used directly in parallel.
38 The fan-out voltage No in the TTL NAND gate parameter refers to the number of gates that can drive the same kind of gate.
39 CMOS integrated gates have higher input impedance than TTL integrated gates.
40 At any time, the state of the output signal of the combinatorial logic circuit depends only on the input signal at that moment.
41 Decoders, counters, full adders, and registers are all logical combination circuits.

42 The encoder can only encode one input signal state at a time.
43 The output state of a digital flip-flop at a certain time depends not only on the state of the input signal at the time, but also on the original state of the circuit.
44 After the digital flip-flop is reset, both outputs are 0.
The 45 dual phase shifter shifts the digital to the left or to the right.
46 Asynchronous counters typically operate faster than synchronous counters.

The 47 N-ary counter can be divided by N.
Compared with liquid crystal digital displays, LED digital displays have the advantages of high brightness and low power consumption.
49 The decimal number represented by the 8421BCD code must be decoded before it can be displayed with a seven-segment digital display.

50 Seven-segment digital displays can only be used to display decimal numbers, not for displaying other information.
The Schmitt trigger converts a slow analog voltage into a phase-changing digital signal.
52 Compared with the successive approximation A/D converter, the double integral type A/D converter has a faster conversion speed but weaker anti-interference ability.
53 The more binary code bits output by the A/D converter, the smaller the quantization error and the higher the conversion accuracy.
54 Digital multimeters mostly use double integral A/D converters.
55 The rated current of various power semiconductor devices is expressed as average current.
56 Two-way thyristors with a rated current of 100A and two anti-parallel common thyristors with a rated current of 50A have the same current capacity.
57 For a gate-off thyristor, the thyristor can be turned on when a positive trigger pulse is applied to the gate, and the turned-on thyristor can be turned off when a sufficient negative trigger pulse is applied to the gate.
58 The minimum gate current required for a thyristor to change from a forward blocking state to a conducting state is called the holding current of the tube.
59 The positive blocking peak voltage of the thyristor, that is, the positive peak voltage applied to the thyristor under the conditions of the gate opening and forward blocking, the value is lower than the turning voltage.
60 Under the specified conditions, regardless of the current waveform flowing through the thyristor, and regardless of the conduction angle of the thyristor, as long as the effective value of the current through the tube does not exceed the effective value of the rated current of the tube, the heat of the tube is allowed.
61 When thyristors are used in parallel, equalization measures must be taken.
62 single-phase half-wave controllable rectifier circuit, regardless of whether the load is inductive or purely resistive, the sum of the conduction angle of the thyristor and the trigger delay angle must be equal to 180°.
63 The maximum phase shift range of the three-phase half-wave controlled rectifier circuit is 0°~180°.
64 In a three-phase bridge half-controlled rectifier circuit, at least two diodes are in conduction at any time.
When the three-phase bridge full-controlled rectification large-inductance load circuit operates in the rectified state, the maximum phase shift range of the trigger delay angle α is 0° to 90°.
66 With balanced reactor three-phase double-reverse star-controlled rectifier circuit, two thyristors are turned on at any time except the natural commutation point.
67 In the three-phase double-reverse star-controlled rectifier circuit with balanced reactor, the average current flowing in each thyristor is 1/3 of the load current.
68 If the load on the thyristor rectifier circuit is purely resistive, the power factor of this circuit must be 1.
The freewheeling diode in the thyristor rectifier circuit only acts to turn off the thyristor in time without affecting the rectified output voltage and current values.
70 If the rate of increase of the voltage across the thyristor is too large, the thyristor may be mis-conducted.
71 DC chopper can change the fixed voltage of DC power supply to adjustable DC voltage output.
72 Chopper's fixed frequency widening mode means keeping the chopper on/off frequency unchanged by changing the width of the voltage pulse. The output voltage average changes when it comes.
73 In the thyristor single-phase AC voltage regulator, two common thyristors or one bidirectional thyristor in anti-parallel are generally used as power switching devices.
74 Inverter is a device that converts DC power into AC power.
75 Passive Inverter is an AC power supply load that converts DC power to a certain frequency or variable frequency.
76 The current-type inverter suppresses the over-current capability better than the voltage-type inverter. It is suitable for the drag device that often requires starting, braking and reversing.
77 In the common domestic thyristor intermediate frequency power supply, the inverter thyristor is mostly loaded. Resonant commutation mode
78 The measurement of transformer temperature is mainly achieved by measuring the oil temperature. If the oil temperature is found to be 10 °C higher than the same load and the same cooling condition, the internal fault of the transformer should be considered.
79 No matter what load the transformer has, as long as the load current increases, its output voltage will definitely decrease.
80 When the current transformer is running, the secondary winding must not open, otherwise it will induce a high voltage, causing personal and equipment accidents.
81 Transformer When the load is idling, the active component of the current is small, and the reactive component is large. Therefore, the power factor of the transformer running at no load is very low.
82 The copper loss of the transformer is measured by no-load, and the iron loss of the transformer is 83 measured by short-circuit test If the primary voltage of the transformer is lower than the rated voltage, its output power must be lower than the rated power regardless of the load.
Welding transformer 84 having a reactor, when the reactor core to increase the air gap, the leakage reactance increases, the welding current increases.
85 If the armature winding of a DC motor is a single-stack winding, the number of parallel branches of this winding will be equal to the number of main poles, and the direction of the induced electromotive force of the armature winding conductor under the same instantaneous adjacent pole is opposite.
86 For the armature winding after rewinding Generally, a pressure test is required to check the quality of the test. The test voltage is 1.5 to 2 times the rated voltage of the motor. When the DC motor is operated under the rated load, the spark level should not exceed 2 grades. The brush has certain requirements on the pressure of the commutator, and the pressure difference between the brushes should not exceed ± 5%.

89 Both the DC generator and the DC motor, the commutating pole winding and the compensating winding should be connected in series with the armature winding.
90 The external characteristic of the DC generator is the same as the excitation current after the generator is connected to the load. In the case of the load terminal voltage varies with the load current.
91 If the load resistance and excitation current of the shunt DC generator remain unchanged, the output voltage will remain unchanged after the speed increases.
92 When the load torque is gradually increased and other conditions are unchanged, the product is recombined. The speed of the DC motor is rising, but the speed of the differential compound DC motor is decreasing.
93 series excitation motor is characterized by relatively large starting torque and overload capacity, and the speed changes significantly with the change of load.
94 Normally, the speed of the DC motor below the rated speed is adjusted, and the change is applied to the armature. The voltage of the terminal; and the speed regulation above the rated speed is to weaken the magnetic flux
95 to weaken the speed of the other DC motor. Generally, the applied voltage should be kept at the rated voltage value, and all the additional resistors should be cut off to keep it weak. After the magnetic flux, the electromagnetic torque of the motor is increased to achieve the purpose of speeding up the motor.
96 In the case that the speed regulation range is large, the voltage regulation speed regulation is the best performance and the most widely used DC motor speed regulation method. The motor changes the armature voltage speed regulation, and the motor excitation should be kept at the rated value. When the working current is rated current, the allowable load torque is constant, so it belongs to constant torque speed regulation
98 DC motor armature series resistance speed regulation is constant torque speed regulation; changing voltage speed regulation is constant torque speed regulation The weak magnetic speed regulation is the constant power speed regulation. The lower the rotor speed of the 99 three-phase asynchronous motor, the larger the slip of the motor, the higher the frequency of the rotor electromotive force.
100 three-phase asynchronous motor, no matter how it is used, its slip rate is always Between 0 and 1
In order to improve the starting torque of the three-phase asynchronous motor, the power supply voltage can be higher than the rated voltage of the motor, thereby obtaining better starting performance.
102 Three-phase asynchronous motor with rated load torque. If the power supply voltage is lower than the rated voltage, Then the current will be lower than the rated current
103 two-speed three-phase asynchronous motor speed regulation, the stator winding from the original â–³ connection to YY connection, the motor pole number can be reduced by half, so that the number of revolutions doubled, The speed control method is a winding rotor asynchronous motor that is driven by a load of constant power. If a frequency sensitive varistor is connected in the rotor circuit to start, the frequency sensitive varistor is characterized in that its resistance value increases with the rotation speed. The automatic improvement and smooth reduction enable the motor to start smoothly. The speed control method of the 105 three-phase asynchronous motor changes the stator winding pole pair speed regulation, changes the power frequency frequency regulation, and changes the rotor slip rate speed. The maximum torque of the three-phase asynchronous motor is independent of the rotor loop resistance value, but the critical slip ratio is proportional to the rotor loop resistance. The maximum torque of the three-phase asynchronous motor is determined. The square of the voltage is proportional to the resistance value of the rotor circuit.
108 DC speed measuring generator, if its load impedance value increases, its speed measurement error increases by 109 electromagnetic DC speed measuring generator, in order to reduce the temperature and cause its output. The error of the voltage can be connected in series in the field winding, which is several times larger than the resistance of the field winding and the temperature coefficient is large. The output characteristics of the hollow cup rotor asynchronous tachogenerator have higher precision, and the rotor inertia is smaller. It can meet the requirements of rapidity.
111 AC tachogenerator, when the excitation voltage is constant frequency and constant voltage AC, and the output winding load impedance is large, the output voltage is proportional to the speed, and its frequency is equal to the frequency of the excitation power supply. Independent speed

112 If the steering of the AC tachogenerator changes, the phase of the output voltage will change by 180 degrees.
113 The output voltage of the resolver is a function of the rotor angle.
114 The structure of the resolver is similar to that of a conventional wound rotor asynchronous motor. It can also be divided into two parts: the stator and the rotor.
The 115-rotor transformer will have a cross-axis magnetomotive force when it is loaded, which destroys the established functional relationship between the output voltage and the rotation angle. Therefore, it must be compensated to eliminate the effect of the AC-axis dynamic potential.
116 sine and cosine rotary transformer, in order to reduce the distortion of the output characteristics during load, the commonly used compensation measures are primary side compensation, secondary side compensation and simultaneous compensation of primary and secondary sides.
117 If the compensation winding of the AC motor amplifier or the commutation winding is short-circuited There will be a phenomenon that the no-load voltage is normal but the voltage drops significantly after the load is applied.
118 The accuracy of the torque-type self-aligning machine is determined by the angular error, which depends on the specific torque and the resistance torque on the shaft. The larger the cross error, the larger the 119 torque motor is a motor that can run at low speed for a long time and can output a large torque. Burned, can not work in the locked state for a long time
120 single-phase series-excited commutator motor can be AC-DC dual-purpose
121 three-phase AC commutator motor starting torque is large, and the starting current is small
122 due to the rotor of the AC servo motor Light and slender, so its moment of inertia is small, the control is more flexible; because the rotor resistance is large, the mechanical characteristics are very soft, so once the control winding voltage is zero, the motor can stop rotating quickly when it is in single-phase operation.
123 AC servo motor is controlled by changing the magnitude, phase or simultaneous change of the voltage applied by the control winding. In most cases, it is working in a two-phase asymmetric state, so the synthetic magnetic field in the air gap Not a circular rotating magnetic field, but a pulsating magnetic field
124 AC servo motor rotates under the control winding current. If the control winding is suddenly broken, the conversion will not stop by itself.
125 DC servo motor generally adopts armature control mode, which controls the motor by changing the armature voltage. The stepping motor is an actuator that converts the electric pulse control signal into angular displacement or linear displacement. Each step of the electric motor is input. The stepping motor rotates one tooth. The working principle of the stepping motor is based on the magnetic force line drawing. By the smallest way, the same reluctance torque as the synchronous motor is generated, so the stepping motor is essentially the smaller the static step error of the stepping motor and the synchronous motor 129, the higher the precision of the motor is 130 steps. The frequency of the highest control pulse that can be applied without entering the motor, called the starting frequency of the stepping motor. 131 The continuous running frequency of the stepping motor should be greater than the starting frequency.

The output torque of the 132 stepping motor increases with the increase of its operating frequency.
133 Automatic control is to apply the control device to automatically control the control object (such as machine, equipment and production process, etc.) according to the predetermined law or change
134 pairs of automatic control. In the case of the system, if the disturbance is generated inside the system, it is called internal disturbance. If the disturbance comes from outside the system, it is called an external disturbance. Both disturbances have an effect on the output of the system.
135 In an open-loop system, since there is no closed loop to the output of the system, the output of the system has no direct effect on the control of the system.
136 Since proportional adjustment relies on input bias To adjust, so there must be a static control system in the proportional adjustment system. The automatic control system with proportional adjustment, there must be static difference
138 integral adjustment can eliminate the static difference, and the adjustment speed is fast
139 proportional integral regulator, the proportional adjustment The function can make the dynamic response speed of the system faster; and the integral adjustment function makes the system basically have no static difference. When the input voltage of the integral regulator is ΔU i=0, the output voltage is also 0.
141 speed control system adopts proportional integral regulator, which takes into account the requirements of no static difference and rapidity, and solves the contradiction between static and dynamic requirements on magnification.
142 Production machinery requires the maximum speed and minimum speed provided by the motor under no-load conditions. The ratio is called the speed regulation range. The difference between the static rate and the mechanical characteristics of the automatic speed control system is no different. The speed range of the 144 speed control system is defined by the ratio of the system speed drop to the ideal no-load speed. The static error rate is the maximum speed and the minimum speed specified by the two unrelated speed regulation indicators 145 in the speed regulation range. They must satisfy the range allowed by the static rate. If the static rate meets the allowable range at low speed, then The rest rate will naturally meet the 146. When the load changes, the DC motor will try to adapt its torque to the load to achieve a new equilibrium.

147 open-loop speed control system can not self-adjust the speed change caused by load change, but the negative feedback control system can be used to improve the mechanical characteristics of the system and increase the speed of the system. In the range 149 control system, negative feedback is used. In addition to reducing system error and improving system accuracy, the system is not sensitive to changes in internal parameters.
150 In a static differential speed control system, the influence of disturbance on output can only be partially compensated. The static speed control system is adjusted by the deviation, while the static speed control system is based on the deviation of the action time. The static speed drop of the 152 speed control system is caused by the voltage drop of the armature loop resistance. The reason why the negative speed feedback can improve the hardness of the system is because it reduces the speed drop caused by the armature loop resistance.
153 The speed negative feedback speed control system can effectively suppress all the disturbance 154 speed control system enclosed in the negative feedback loop. In the middle, the voltage differential negative feedback and the current differential negative feedback link are involved in the adjustment of the 155 speed control system in both dynamic and static systems. In the middle, the current cut-off negative feedback is a link that only acts as a negative feedback adjustment under the overcurrent condition of the main circuit of the speed control system, and is used to limit the overcurrent of the main circuit. Therefore, it belongs to the protection link 156. And the voltage negative feedback is to improve the hardness characteristics of the DC motor and expand the speed range.
157 speed control system positive feedback, essentially a load torque disturbance feedforward speed control system 158 voltage negative feedback speed control system static characteristics better than the same magnification of the speed negative feedback speed control system 159 voltage negative feedback speed regulation The system can not adjust the speed change caused by the armature resistance and excitation current of the DC motor.
160 In the thyristor DC speed control system, the torque of the DC motor is proportional to the armature current and proportional to the current effective value of the main circuit.
161 The mechanical characteristics of 161 thyristor DC speed regulation system can be divided into continuous section and discontinuous section. The occurrence of discontinuous section characteristics is mainly because the thyristor conduction angle θ is too small, so that the current interruption 162 is used to limit the speed control system startup. Current, thyristor 163 can be protected by overcurrent relay or fast fuse to protect the main circuit.
Double closed loop DC automatic speed control system includes current loop and speed loop. The current loop is the outer loop, the speed loop is the inner loop, and the two loops are connected in series, also known as the double loop cascade speed regulation.
During the starting process of the 164 double closed-loop speed control system, the current regulator is always in the regulation state, and the speed regulator is in the adjustment state at the beginning and the end of the starting process, and is in a saturated state in the middle stage.
165 due to the stall current and the turning point of the double closed-loop speed control system The current difference is very small, so the system has an ideal "excavator special type"
The reactor of the main circuit of the 166 reversible speed control system is a balanced reactor, which is used to limit the ripple current 167. In the anti-parallel reversible circuit of the two sets of thyristor converters, the working states of the positive and negative thyristor converters must be strictly controlled. Otherwise It is possible to generate a circulating current 168 reversible speed control system main group rectifier device operation, reverse group rectification to be inverted, and let its output voltage Udof = Udor, so there is no circulation in the circuit 169 for the irreversible speed control system, you can use two groups Anti-parallel thyristor converter for fast feedback braking
170 Reversible adjustment The system reversal process is connected by the forward braking process and the reverse starting process. In the forward braking process, the two stages of the bridge inversion and the anti-bridge braking are included.
171 Two sets of thyristor converters in the anti-parallel reversible speed control system, when the control voltage Uc=0, the zero points αfo and βro of the control angles of the two sets of trigger devices are both set to 90 degrees.
172 In a logic loopless speed control system, there must be a logic loopless device DLC to control the blocking and opening of the two sets of pulses. When the switching command is issued, the DLC immediately blocks the original conduction group pulse and simultaneously opens another group of pulses to realize the switching of the positive and negative thyristors. Therefore, the system is loopless.

173 In some AC power supply situations, the chopper can be used to realize the voltage regulation of the AC motor.
The 174 cascade speed regulation does not string the resistor in the rotor circuit, but the additional electromotive force is added to change the slip rate. speed. Compared with the string resistance speed regulation in the rotor circuit, the maximum advantage of the cascade speed regulation is the high efficiency. The hardness of the mechanical characteristics during the speed regulation is unchanged.
The 175 series speed regulation is the same as the series resistance speed regulation. Speed regulation method 176 cascade speed regulation can add the slip power added in the additional electromotive force to the grid or the motor shaft, so it belongs to the slip power feedback type speed regulation method 177 in the rotor circuit stringing in the additional DC electromotive force. In the cascade speed control system, only the mechanical characteristics of the 178 open-loop cascade speed control system with low and synchronous speed can be achieved. The mechanical characteristics of the asynchronous motor are softer than that of the asynchronous motor.
179 frequency conversion speed regulation performance, large speed range, good smoothness, low speed characteristics, is an ideal speed control method for cage rotor asynchronous motor 180 frequency conversion speed regulation device, its function is to keep the grid constant The constant-frequency alternating current is converted into a variable-voltage variable-frequency alternating current, and the alternating-current motor is supplied with power to realize the AC stepless speed regulation.
181 In the frequency conversion speed regulation, in order to obtain the constant-speed speed regulation characteristic, the magnetic flux φm of the motor should be used as much as possible. Keep the rated value unchanged 182 When the frequency conversion speed regulation is maintained, if the power supply voltage of the motor stator is kept constant, only changing the frequency to carry out the frequency conversion speed regulation will cause the change of the magnetic flux, and the phenomenon of insufficient excitation or excessive excitation will occur. The basic control method is constant flux frequency regulation below the rated frequency and the weak magnetic speed regulation above the rated frequency.
184 AC-AC conversion is to rectify the commercial frequency AC to DC, and then invert from DC to the required frequency. AC 185 AC-DC-AC inverter converts the power frequency AC power into DC power through the rectifier. After the intermediate filter link, it is transformed into the inverter voltage conversion by the inverter. Streaming, so called indirect converter 186 sine wave pulse width modulation (SPWM) refers to the reference signal is a sine wave pulse width modulation mode 187 In the bipolar SPWM modulation mode, the reference signal and carrier signal are bipolar Sexual signal 188 In the unipolar SPWM modulation mode, the reference signal is a unipolar signal and the carrier signal is a bipolar triangular wave 189. In the SPWM modulation mode inverter, as long as the amplitude of the reference signal sine wave is changed, The inverter output AC voltage can be adjusted in the size of the inverter. In the inverter of the SPWM modulation mode, the frequency of the inverter output AC voltage can be changed by changing the frequency of the carrier signal.
191 The variable frequency speed control system adopting the closed-loop vector-speed control of the speed can basically achieve the dynamic performance of the DC double-closed loop system, thus it can replace the DC speed control system.
The 192 programmable controller (PC) is composed of an input part, a logic part and an output part. The input part of the 193PC is to process the acquired information and react according to the actual action requirements of the controlled object.
194 The microprocessor CPU is a PC. The core, he directs and coordinates the entire working process of the PC.
The memory of the 195PC is divided into two categories: system program memory and user program memory. The former generally uses a RAM chip, and the latter uses a ROM chip 196PC.
The working process is a periodic cycle scan, which is basically divided into Three phases are performed, both the input sampling phase, the program execution phase, and the output refresh phase.
197 Ladder diagrams must conform to the principle of execution from left to right and top to bottom.
198 In the ladder diagram of the PC, the coil of the soft relay should be directly connected to the right busbar, but not directly to the left busbar.
199 In the ladder diagram of the PC, all the soft contacts can only be connected to the left side of the soft relay coil. Cannot be directly connected to the right bus.
Each soft relay in the 200 ladder diagram must be a soft relay within the allowable range of all machines.

201 Programmable Controller Inputs, Outputs, Auxiliary Relays, Timers, and Counters are all limited.
202 Since the PC operates in a periodic cyclic scan mode, there is no requirement for the order of the various instructions in the program. The PC application with the same control task in advance is the only 204 input relay for receiving the switching signal of the external input device, so the coil and contact 205 are not present in the ladder program. The coil of the auxiliary relay is driven by the program. The contact is used to directly drive the external load.
206 The soft relay with power-down hold function can have a lithium battery to keep it in the state before the PC is powered down.
207 F1 series PC, the number of the soft relay is represented by three decimal digits.
208 F1 series PC In the middle, the counters have the power-down hold function, and both are the addition counter 209. When the power of the PC is powered down, the status relay is reset. In the F1 series PC, all the shift registers have the power-down hold function 211. The counter using the F1 series PC. When it is assigned to the initial value of 0
When the 212 OUT command drives the timer coil, it can be used to drive various relay coils.
213 When the timer coil is driven by the OUT command, the program must use the following K and 3-digit octal numbers to set the desired timing. Time
214 After using the master command MC, the position of the bus will change accordingly.
215 Using CJP and EJP instructions, some programs can be skipped when the conditions of CJP are satisfied, and the following programs of EJP instructions can be executed, but the conditions in CJP cannot be satisfied. When the program is executed in the original order, when multiple CJP instructions are nested, if the conditional transfer of the outer layer can be executed, the conditional transfer of the inner layer is invalid.
217 Replace the written instruction with the NOP instruction, and have no effect on the ladder configuration.
218 Only the state controller that uses the S command is set to have the step control function.
219 After using the STL instruction, the LD point is always stepped. On the right side, the starting contact connected to the step contact is to be commanded with LD or LDI. Use the RET instruction to return the LD point to the bus

220 When writing a program to the programmable controller, first clear the memory and then write the program according to the operation instructions. At the end, use the end instruction 221 to use the END instruction to debug the user program in sections 222. Digital control uses digitized information. A control technology for controlling the controlled object 223 Modern CNC system is mostly computer numerical control system 224 for different models of computers, assembly language programs written for the same problem, can be mutually common 225 programs written in assembly language, must By compiling into the corresponding machine language, the computer can directly execute 226 assembly language suitable for programming in industrial control and smart meters. 227. The numerical control device is the control core of the numerical control machine tool. It performs numerical calculation according to the input program and data. Logical judgment, input and output control, track interpolation and other functions.
228. The servo system includes a servo control circuit, a power amplifying circuit, a servo motor, a mechanical transmission mechanism, and an actuator. The main function of the servo system is to convert the interpolation pulse signal generated by the numerical control device into the motion of the machine tool actuator.
229. CNC machining program is composed of several program segments, the program segment is composed of several instruction codes, and the instruction code is composed of letters and numbers.
The 230.G code is an instruction to prepare a CNC machine for a certain type of motion.
The 231.M code is mainly used for the switching control of CNC machine tools.
232. In the numerical control machine tool, the coordinate axes X, Y, and Z of the linear motion of the machine tool are defined as the right-hand Kadir coordinate system.
233. In CNC machine tools, the positive direction of the tool movement is usually used as the positive direction of programming.
234. A basic unit of length that the table moves under the action of a pulse, called the pulse equivalent.
235. The control accuracy and feed rate of the point-by-point comparison method are low, which is mainly applicable to the