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Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin
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inductance
Before explaining this question, explain several terms: active power, reactive power, and apparent power.
Active power: In the AC circuit, the part of the power (such as converted to thermal energy, light energy, or mechanical energy) that is consumed by the irreversible power on the resistive element is called active power;
Reactive power: In a circuit, an inductive component establishes a magnetic field. The power that the capacitive component establishes to consume an electric field is called no power. This power is continuously converted with the power source according to the cycle of the alternating current, and does not consume energy;
Apparent power: The total power that AC power can provide is called apparent power. In terms of value, it is the product of voltage and current. Unit VA, apparent power is the capacity of AC power.
Resistive load:
That is, when the load current load voltage has no phase difference compared with the power supply, the load is resistive (for example, the load is a white light, an electric furnace, etc.)
In a nutshell, a purely resistive load that works only with resistive components is called a resistive load.
Inductive load In general, the load with the inductance parameter of the load is generally inductive (such as the load as the motor; the transformer;) that meets the characteristics of the phase difference between the load current and the load voltage. In layman's terms, high-power electrical products, such as electric motors, compressors, relays, fluorescent lamps, etc., which are manufactured using the principle of electromagnetic induction.
This type of product requires a much larger starting current (approximately 3-7 times) than the current required to maintain normal operation. For example, a refrigerator that consumes about 150 watts of electricity during normal operation can have a starting power of more than 1000 watts.
In addition, because the inductive load is connected to the power supply or disconnected from the power supply, a potential voltage is generated, and the peak value of the voltage is far greater than the voltage value that the vehicle AC power supply can withstand, which easily causes the vehicle inverter. Instantaneous overloading affects the life of the inverter. Therefore, such appliances have higher requirements for power supply waveforms.
A capacitor-like load in a capacitive load circuit can cause the load current to advance the load voltage by a phase difference (compared to the power supply) and reduce the circuit power factor.
The load with the capacitance parameter of the load, that is, the load that meets the characteristics of the voltage hysteresis current is generally made into a capacitive load. When charging and discharging, the voltage cannot be abruptly changed.
Its corresponding power is negative. The power factor of the corresponding inductive load is a positive value.
For general power control products, the given load, if not stated, is the apparent power; that is, the total capacity power; it includes both active power and reactive power;
The general inductive load description is often given the amount of active power, such as fluorescent lamps, fluorescent lamps labeled 15 to 40 watts, ballast power consumption is about 8 watts, the actual use of timers, the sensor switch is controlling it When you add this 8 watts;
The specific inductive part of the product, ie the magnitude of the reactive power, can be calculated from its given power factor.
In the hybrid circuit, the capacitive reactance is more sensitive, and the circuit is capacitive and vice versa.
There is no pure inductive load and pure capacitive load in the usual electrical appliances. Because these two loads do not do useful work.
Pure inductive or pure capacitive loads are only used in the compensation circuit. Because most of the load is resistive, most of them are inductive loads. Therefore, most of the compensation is compensated by capacitors. Therefore, pure capacitive loads are used more than pure inductive loads. Such as electric motors, transformers, etc., usually inductive loads. Some fluorescent lamps are capacitive loads.
Example:
A purely inductive load is a set of inductors. Usually used to compensate for capacitive currents in the circuit.
In a circuit with a coil in a circuit, the coil portion is a purely inductive load. Such as motors, transformers, electric fans, fluorescent lamp ballasts, etc.
The current of a purely inductive load cannot be mutated. Inductive loads are widely used. In a circuit with a capacitor, the capacitive part is a pure capacitive load. Such as compensation capacitors.
The voltage of a purely inductive load cannot be mutated. In theory: pure resistance circuit, pure capacitance circuit, pure inductance circuit does not exist.
Resistive loads also have inductive and capacitive loads when working. For example, there will be capacitance between the wires between the wires, and there will be inductance between the wires and between the wires, and the inductive load is usually larger than the capacitive load. Power capacitors also generate heat when working, that is, resistive work. The same is true for inductors. The impedance of a component is a function of frequency. Pure resistance circuits, pure capacitance circuits, and purely inductive circuits do not exist in the full frequency range.
In theory, it is only possible to exist at a certain frequency. In practice, it should not be done.
1. Harmonics: The frequency of China's power grid is 50Hz. Any wave with a frequency higher than 50Hz is called harmonic. Harmonics are generated in multiples, that is, the frequency is a multiple of 50: 100, 150, 200... Any wave above 50 Hz is called a high harmonic.
Second, load: refers to the device that consumes electrical energy, converting electrical energy into mechanical energy, thermal energy, light energy, and the like. The load refers to the use of electrical appliances, such as: lighting, lamps, electric furnaces, motors, refrigerators, air conditioners, etc.
Third, light load: Light load mainly refers to the equipment driven by the motor is relatively light, does not reach the rated power of its design, that is, the actual load is less than the design load.
4. Variable load: Variable load refers to the load that the motor is moving during the operation. It is constantly changing, sometimes heavy, sometimes light, and the power output to the motor is sometimes large and sometimes small. When the voltage is constant, the current changes as the load changes. For example: jaw crushers, various presses, stamping machines, pumping units, compressors, hydraulic presses, electric sewing machines, etc.
5. Dead load: The dead load is also called fixed load. When the motor is running, the load is basically unchanged. The output power and current of the motor are basically a constant value. Light loads may be dead loads.
6. Overload operation: Overload operation means that the motor is in an operation that exceeds its own load capacity. For example, a 55KW motor rated current is 110A, and in actual operation, the current exceeds 110A, which is overloaded operation. Equipment that has been overloaded for a long time will be damaged and its service life will be reduced.
7. Load ratio: The load ratio is the ratio of the actual operating current to the rated current. Load rate = actual working current ÷ rated current × 100%
Eight, the relationship between the rated power of the motor and the rated current: Generally speaking, the rated current of the motor is twice the rated power.
For example: a 37KW motor, its rated current is about 37 * 2 = 74A
A 100KW motor with a rated current of approximately 100*2=200A
Nine, inductive load, resistive load: For the luminaire, the luminaire that is illuminated by gas is the inductive load, and the resistive wire is a resistive load. The inductive load is such as: fluorescent lamp, high pressure sodium lamp, mercury lamp, metal halide. Lights, etc. Resistive loads such as: iodine tungsten lamps, incandescent lamps, resistance furnaces, ovens, electric water heaters, hot oils, etc. The motor is also an inductive load.
X. Actual working current of several common lights: (in the case of grid voltage 220V)
1, 400W high pressure sodium lamp single lamp, working current is 3.1 ~ 3.3A.
2, 250W high pressure sodium lamp single lamp, working current is 2.0 ~ 2.3A.
3, 400W metal halide lamp single lamp, working current is 2.0 ~ 2.2A.
4, 250W metal halide lamp single lamp, working current is 1.4 ~ 1.6A.
5, inductive ballast 40W fluorescent lamp single lamp, working current is 0.28 ~ 0.30A.
6, electronic ballast 40W fluorescent lamp single lamp, working current is 0.14 ~ 0.16A.
According to the above data, the lamp consumes electricity in addition to the light itself.
Control Valve, Flow Control Valve, Hydraulic Control Valve, Proportional Directional Control Valve
