What is the normal current of a 3KW three phase motor?

General AC motors, including frequency modulation motors, are not allowed to be blocked. According to the external characteristic curve of the AC motor, when the AC motor is stalled, it will generate a "subversive current" to burn the motor. At this time, if the inverter adopts vector control, the motor is stalled, and the torque current is not controllable.

I've experimented with this. If the speed exceeds 5Hz, the torque current can be controlled (the size can be adjusted smoothly), and the encoder feedback is better than the non-encoder feedback.

Therefore, for ordinary AC machines, open-loop control and motor stall can not control the stall torque. If the servo AC motor is used, the closed-loop speed control, angle control, and position control can be blocked.

For ordinary motors, you can consider that the robot is artificially locked or stuck, and the forced lock-up has been completed, and the user's process requirements have been completed, and then the mechanical lock-up mechanism is released for the next process control. AC motors are easy to burn out if they are stalled or missing phase (especially for two-pole motors). First of all, we must understand the DC resistance of the motor winding, its DC resistance is below 15 (the greater the motor power, the smaller the DC resistance, some are less than 1), if the motor loses the AC inductance when the stalled or phase is missing, then the circuit resistance of the motor is only below 15, and the current at this time can be imagined how big (take 380V, for example:

380 15 = 25, 25A current has far exceeded the overcurrent value of the motor coil). Therefore, the motor is generally equipped with phase loss and overcurrent protection (all circuits through my hands are equipped with phase loss and overcurrent protection), once the motor has a problem, the first thing is that the current changes, so that it will play a role in protecting the motor.

The rated current of a 3 kW three-phase motor.

It should be 6**.

The formula for calculating the current of the electric motor:

Three-phase motor Power 1 kW 2 (A) per phase Current (A) = Power (kW) W) * 1000 Force Rate * Efficiency (Note: Force Rate:; Efficiency:

The formula for calculating the current of the electric motor:

Three-phase motor Power 1 kW 2 (A) per phase Current (A) = Power (kW) W) * 1000 Force Rate * Efficiency.

Remarks:Force Rate:; Efficiency: The rated current of the kilowatt three-phase motor should be 6**.

The motor is lightly loaded. As a rule of thumb, a 380V three-phase motor has a current of about 2A for 1kW; Then the 3kw current should be 6A, and the actual rated current should be slightly larger than 6A. However, the three-phase current of the 3kw motor in the title is significantly lower than the rated current.

So why is the actual current of the motor smaller than the rated current? I think the main reason is that the load on the motor is too light. The greater the load on the motor, the greater the current; The smaller the motor load, the lower the current.

If the actual current exceeds the rated value for a long time, then the coil will burn out due to overheating.

When the motor is unloaded, the no-load current will be much lower than the rated current. The no-load current of the low-power motor is generally about 50% of the rated current, and the no-load current of the high-power motor is generally about 30% of the rated current. The motor runs no-load or light-load for a long time, and due to the high proportion of no-load and light-load no-load excitation current, the motor is in the state of "big horse-drawn trolley" at this time.

Then the efficiency of the motor is low, the power factor is low, and a lot of reactive current needs to be absorbed from the power grid, which increases the line loss of power supply, which is not conducive to the operation of the power grid.

Therefore, when choosing the power of the three-phase motor, the motor can not be too small, nor can it be too large. If the motor power is just equal to the load power, the motor may be overloaded when the load fluctuates. Generally, it is more appropriate to ensure that the actual power accounts for 80%-95% of the rated power when the motor is selected.

Three-phase imbalance.

According to the national standard, the unbalanced current shall not exceed 10% when the motor is working normally. Let's first calculate the current unbalance of the motor.

So what are the possible causes of the current imbalance of the motor? I think there are several possibilities:

1.Three-phase voltage imbalance.

When the voltage of the three-phase motor is unbalanced, the three-phase current will vary greatly. We can measure the voltage of each phase through the multimeter to see whether the voltage of each phase is within the allowable range, and the general three-phase voltage unbalance is not allowed to exceed 5%. In addition, when the voltage of the three-phase motor is unbalanced, the electromagnetic noise of the motor will also become much larger.

If you find that the motor noise is too loud, see if the motor current is normal, and check the specific cause.

2.Problems with the motor itself.

It may be that the motor winding is not well insulated, the turn is short-circuited, or the motor quality is not good, and the number of winding turns is too different. We can measure the three-phase winding through the bridge to see if the resistance value is the same, and the unbalance of the three-phase resistance is required not to exceed 4%.

3.Lines are a problem.

Finally, there is another possibility of line problems, such as the contact resistance of a certain phase of the switch is too large, resulting in uneven line voltage; Or the cross-sectional area, material, and length of the three-phase wire are not equal, resulting in the resistance of the three-phase wire is not large.

In real life, we often use a 3kw motor, so what is the current of a 3kw motor?

1. How much current is a 3 kilowatt motor?

Generally speaking, the power of the motor is about 17A, and the current of the 3000 watt single-phase motor is about 17A, and the current of the three motors is about 17A.

If it is 220V, then the current of the 3000 watt motor is about the same. Generally, the 1kW of a single-phase motor is calculated according to the current, while the 1kW of a three-phase motor is calculated according to the current of 2A. The 660V motor 1kW is calculated according to the current.

2. What do 3KW and 3KW-2 mean?

3kw refers to the power of the machine output by the motor itself, not the power input, and is equal to the output power divided by the mechanical efficiency divided by the power factor. For example, the efficiency of the machine is, and the overall factor of power is around, then the power to be input by the 3kw motor is.

KW refers to kilowatts, 1kw is equal to the power consumption of 1kw power electrical appliances when it works normally, 1 kilowatt electrical appliances, it will consume one degree of electricity when it works normally, so it is called the number of stages of the motor, the smaller its progression, and the higher its own speed, the smaller the relative torque, the general series are multiples of two. There are four and six, there are eight levels, and so on.

The specific performance of the motor is to produce a certain driving distance, so that electrical appliances and various machinery can be used as the power source of electrical appliances or various machinery. The generator is generally represented by G in the circuit, and its main role is to use mechanical energy to convert into electrical energy, and the most widely used way is to use electrical energy and water energy to drive the generator to generate electricity.

The normal current of a 3kw three-phase motor is 6 amps, and the starting current is 6 to 7 times the rated current.

Ordinary three-phase asynchronous motor, 3kw belongs to a small-capacity motor, and the power factor is about the efficiency. Therefore, the current is about: 3 [. Due to the large number of motor models and large technical differences, the current is normal on the left and right.

For 3kw three-phase motors, the rated current is generally about about one.

Solution: Generally, the current of 1kw of three-phase motor is force rate x efficiency) = 2a. So the current of the 3kw motor is about 6A.

The three-phase asynchronous motor with a power of 3kw and a voltage of 380v has a rated current of about 6A if it is a standard 4-pole motor.

Hello, the normal current of the 3kw three-phase motor is 6A, I hope mine can help you, if you are satisfied!

According to the empirical formula, the rated working current of the three-phase asynchronous motor is about 2 times of its power, that is, the rated current of the 3kw three-phase asynchronous motor is 6A.

3-phase 380, 3kw motor working current should be 6A current.

The current calculation formula of the motor Three-phase motor Power 1 kW 2 (A) per phase Current (A) = Power (kW) W) * 1000 Force Rate * Efficiency Remarks: Force Rate:; Efficiency: The rated current of the kilowatt three-phase motor should be 6**.

The current is about seven amperes, and the current of the power line is really helping you look forward to it.

3kw motor type, current is not the same, if you wiring, can be estimated according to 2a per kw, increase the point safety factor, if you measure the motor debt ratio to see the signage.

Three-phase electricity can be calculated in terms of approximately one kilowatt 2a.

Let's do the math if the motor is rated.

is 380V, then the motor rated current.

i=p/。

The rated current of Y2 series motor is: A (2 poles.)6 A (4 poles.)8 A (6 poles.)2 amps (8 poles).

The current of a three-phase motor (1 kW) is:

The power calculation formula of the three-phase motor is: p=, so the calculation formula for the current is:

i=p (is the motor power, u is the three-phase electric voltage, cos is the motor power factor, generally taken.)

Summary. 1. The current formula of the three-phase motor: i=p (, cos is the power factor.

2. If U=380V, the COS is generally about under the rated working conditions. Substituting the formula can be obtained, in terms of numerical value, i=, generally take 2 times the relationship, therefore, the motor current of 1kw is about 2A, but the current may be slightly different due to the number of poles, factors and types of the motor.

Substituting the formula can be obtained, in terms of value, i=, generally take 2 times the relationship, therefore, the motor current of 1KW is about 2A, but the current may be slightly different due to the number of poles, factors, and different types of burial types of the motor.

3KW, the current of the three-phase asynchronous motor is about 7A, and the rated current of the motor is also related to the number of poles and efficiency of the motor.

The rated current of the 3kw motor is about and so, and it should not be greater than this number when it rotates normally.

3kw three-phase 380v motor.

The rated current is 6A

380V electric motor (three-phase air conditioning compressor.

The formula for calculating the current is: i rated power.

Rated voltage power factor.

Efficiency:For example, if the power factor of a 10 kW motor is, then i = 10000 x 380 x = 16a.

The direction of the current moves in the circuit with a positive charge.

in the same direction. It is not the positive charge that actually moves, but the negative charge moves. The flow of electrons is the movement of electrons (negative charges) in a circuit in the opposite direction of the electric current.

The power factor is the power system.

An important technical data. The power factor is a factor that measures the efficiency of electrical equipment. A low power factor indicates the reactive power of the circuit for alternating magnetic field conversion.

large, thereby reducing the utilization rate of the equipment and increasing the loss of line power supply.

P= 3UICOS ,P motor power kw,U motor rated voltage V,i motor rated current a,cos motor power factor (generally take the value), efficiency (generally take the value, there is an empirical formula, 380V three-phase motor current is 2 times of its rated power, according to the power and the number of poles are different.

How much current does a 380v three-phase motor have, and how much current does the motor have is determined by the power of the motor.

The maximum instantaneous current three-phase alternating current is a multiple of the rated current.

The maximum working current of the motor is the working current that the motor can work for a long time, which can reach about twice the rated current, and the motor selection is small due to improper calculation of the design power. Tease.

However, in the case of exceeding the rated power, the motor can continue to work, at this time, the working current of the motor is the maximum working current, and the starting current of the motor = stalled current = maximum current.