How to calculate the starting capacitance of the motor, and how to calculate the starting and runnin

The formula for calculating the working capacitance of a single-phase motor is: GC=1950I UCOS (micro-method) where: i: motor current, u: single-phase power supply voltage, COS: power factor, take, 1950: constant.

After calculating the working capacitance of the single-phase motor, the starting capacitance is calculated as 1-4 times of the working capacitance.

How to calculate the starting and running capacitance of the motor? Hello dear, the formula for calculating the working capacitance of a single-phase motor: GC=1950i UCOS (microfar) where:

i: motor current, u: single-phase supply voltage, cos:

Power factor, Take, 1950: After the working capacitance of the single-phase motor is calculated by constant, the starting capacitance is calculated by 1-4 times of the working capacitance. Calculate the operating capacitance = 1950 * motor current (power supply voltage * power factor), the power factor is taken, 1950 is the constant.

Calculation of starting capacitance: Usually calculated as 1-4 times the operating capacitance capacity. Capacitive induction motors have two windings, namely the starting winding and the running winding.

The two windings differ by 90 degrees spatially. A capacitor with a large capacity is connected in series on the starting winding, and when the running winding and the starting winding pass through a single-phase alternating current, the current in the starting winding is 90 degrees ahead of the current of the running winding in time due to the action of the capacitor, and reaches the maximum value first.

Summary. How to calculate the starting and running capacitance of the motor? Hello, how to calculate the starting and running capacitance of the pro-motor?

How to calculate the starting and running capacitance of the motor? Hello, how to calculate the starting and running capacitance of the pro-motor?

How to calculate the starting and running capacitance of the motor? Hello, pro C=1950I UCOS (micro-method) single-phase motor operating capacitance calculation formula: C=1950i UCOS (micro-method) male bucket hit-type in:

i: motor current, u: power supply electric voltage; cos∮:

Power Factor, 1950: Constant. The starting capacitor is generally calculated as 1-4 times the operating capacitance capacity.

The capacitance of the click is calculated according to the starting current of the motor, not at no-load, but by load, and the capacitance calculated by no-load, and the motor cannot be started under load. Generally, a small motor is 5 times the rated current calculation, a 200 watt capacitive motor, the rated current is about 1 amperere, then the capacitance is calculated by 5 times the rated current of the motor. Then dividing 220 volts by 5 amps equals 44 ohms.

Multiplying 44 ohms by 50 hertz is equal to 2200, and then dividing by one, it is equal to, because the carry relation of capacitance is in millions, 1 farad = 1,000,000 microfarads; 1 micro farad = 1000000 micro farad, so it will be converted into micro farad, the capacitance value is 4550 micro farad (uf), the voltage selection calculation of the capacitor is the root number multiplied by 220 volts AC voltage, that is, multiplied by 220 volts, the value obtained is the capacitor withstand voltage value. Generally, a withstand voltage of 400 volts is sufficient, for reference only.

DC motors. No configuration is required.

Starting capacitor. The start-up capacitor is used for:

AC motors. Middle.

Working principle: single-phase motor.

The single-phase current flowing through it cannot produce a rotating magnetic field, and capacitors are required to divide the phases in order to produce a current in the two windings that is close to 90.

Phase. to create a rotating magnetic field.

Capacitive induction motors have two windings, namely the starting winding and the running winding. The two windings differ by 90 degrees spatially. A capacitor with a large capacity is connected in series on the starting winding, when the running winding and the starting winding pass.

Single-phase alternating current.

, due to the action of the capacitor, the current in the starting winding is 90 degrees ahead of the current of the running winding, and reaches the maximum value first. At.

Time and space.

two identical pulsed magnetic fields are formed so that the stator and the rotor are combined.

between. Air gap.

A rotating magnetic field is generated, and under the action of the rotating magnetic field, the motor rotor.

generated. Induced current.

The electric current interacts with the rotating magnetic field to produce an electromagnetic field torque, which spins the motor.

To make. Single-phase electric motors.

It can be automatically rotated, we can add a starting winding in the stator, the starting winding and the main winding are 90 degrees different in space, and the starting winding should be connected in series with a suitable capacitor, so that the current with the main winding is approximately 90 degrees different in phase, that is, the so-called phase splitting principle. In this way, two currents that differ by 90 degrees in time flow into two windings that differ by 90 degrees in space, and a rotating magnetic field (two phases) is generated in space. Under the action of this rotating magnetic field, the rotor can start automatically, and after starting, when the speed rises to a certain level, it is installed on the rotor with the help of a rotor.

Centrifugal switch. or other automatic control devices will disconnect the starting winding, and only the main winding will work when it is working normally. Therefore, the starting winding can be made to work for a short time.

But there are many times, the starting winding is not opened, we call this kind of motor capacitive single-phase motor, to change the steering of this motor, you can change the position of the capacitor in series.

Do DC motors need to distribute capacitors? Are you sure? AC asynchronous motor should be equipped with starting capacitor, some should be equipped with double capacitors, one to start and one to run, AC synchronous motor does not use capacitor to start, DC motor distribution capacitor is the first time I have heard of it, and I don't know why, what is the use. Hehe.

Halo, you should be talking about AC motors, generally the starting capacitance is between 60 100U, and the operating capacitance is 10 15U.

The capacitance of the line capacitor can be calculated as follows: c=1950*in (un*cos).

f) in the formula, in, un, cos ten are the original three-phase motor nameplate on the rated current, rated voltage and power factor value, if there is no power factor on the nameplate, cosy can take 0 85 or so.

The capacity of the starting capacitor can be selected according to the size of the load when the motor is started, which is usually 1 4 times that of the operating capacitance. For small motors with a power of less than 1kw, the starting can also be removed, and the value of the operating capacitance should be appropriately increased. After this reconnection, the capacity of the motor will be reduced by 10 40 according to the size of the power factor when the motor is running.

1 The connection mode of the motor when it is running in single phase.

1) Triangular connection of three-phase winding.

Connect the capacitor to either end of any phase of the three-phase winding (in the figure it is connected to both ends of the U phase), and then add 220V mains power to one end of the capacitor C and the intersection of V2 and W1. In this way, the motor can be rotated, and if you need to change the direction of rotation of the motor, you can switch the mains power from one end of the capacitor to the other.

2) Star connection of three-phase winding.

Connect the capacitor to any two terminals, and add the 220V mains power to either end of the remaining terminal W1 and capacitor C. In this way, the motor can be rotated. If you need to change the motor steering, you can change one end of the mains power from U1 to V1.

2 Capacitance selection of capacitors.

When the small three-phase asynchronous motor is used for single-phase operation, the selected capacitor capacity must be appropriate, if it is too small, the rotation will be weak and the start will be difficult; If it is too large, the loop current will be too large, causing the motor to overheat.

The capacitance of the starting capacitor can also be obtained by empirical formula: when the star is connected, the required capacitance c(f) p(w) 17, the unit of c is f, and the unit of p is w;When used as a triangle wire, the selected capacitance c(f) p(w) 10.

The operating capacitance can be calculated by 25 micromethods per kilowatt, and the starting capacitance can be about 4 times the operating capacitance.

The operating capacitance of the single-phase motor can be selected according to 1-4UF per 100W. (i.e., 1000W should be selected C-Yun = 1000 100*2 (micro-method)).The starting capacitance should be selected 4-10 times the working capacitance (i.e.:

c from = 20 * 10 = 200 uf micro-method).Why should 1000w single-phase motor be chosen 10 times?Because single-phase motors above 1000W require a larger starting distance, 10 times is chosen.

When the three-phase motor is running in single-phase operation, the required capacitance is working, and the voltage at both ends of the capacitor is 110V, which is the best.