Full range of Motor Start Capacitor manufacturer in China

How to Choose Motor Start Capacitor

MicrAs an electrician, it is common to replace the starting capacitor of the motor. Some of them are very easy. The model to be replaced is usually based on the principle of original replacement. However, sometimes there are some special cases. For example, the starting capacitor of the motor is severely burnt out and deformed, and the model parameters marked above can not be seen at all. Or if there is no same model around us, do we know the model parameters of the capacitor to be replaced quickly? Here are three methods. You can choose a suitable one according to your hobbies!

The first method is rote memorization. Here is an order. According to the motor power from small to large, 40-60 watt motors are generally equipped with a capacitor of 1-1.5uf capacity, 70 watt motors are generally equipped with a capacitor of 2uF capacity, 180 watt motors use a 6UF capacitor, and 350-2.2 kW motors use 450v200 μ F nonpolar capacitor is unnecessary to calculate, because the operating current has an allowable range. It is not difficult to remember these. You can know the starting capacitor model to be replaced as soon as possible. It should be emphasized that the starting capacitor and the working capacitor should be noted here, because the starting capacitor actually requires a larger current than the working capacitor, but because the capacitor selection can allow a certain floating range, most of them choose the working capacitor to be a little larger for both purposes, which means that some electric fans can not be started when they are started because they have been used for a long time and the capacitor loss has become smaller, Just change a capacitor with a larger capacity. The second method is more theoretical and has a slightly higher accuracy. However, some factors are the estimation of components, so the result is not very accurate. The drawback is that sometimes it is a little idle and troublesome. However, if you are familiar with the calculation for several times, the palm method is the same as calculating a calculation problem. It is not as complicated as you think. Various parameters are brought into the formula, and the circled result is to select the capacity of the capacitor, Calculate and select according to the following formula: c=350000*i/2p*f*u*cos ∮, where: CO ∮ refers to the motor power factor, generally 0.55—0.75 P refers to the motor pole pair, which is available on the motor nameplate or can be calculated according to the formula

U refers to the power supply voltage. In the rated state, f refers to the power frequency. In China, it is 50Hz, l refers to the rated current, and C refers to the capacitance capacity. The last method is the fastest and most accurate method. It is the electrician calculation software in the mobile phone. Download an electrician calculation software, fill in the parameters to be calculated, and the software will automatically calculate the capacity of the selected capacitance, which benefits from high technology.

Finally, here is the key point. This is also a summary of experience. If we can’t buy the estimated or calculated capacitance or don’t have it at hand, we can choose the nearest model with similar capacity and try to be larger. However, no matter which method is used for selection, we must check whether the current is consistent after the final replacement. The final results have been based on this test to determine whether the selected capacitance is appropriate. If the current difference is too large, It indicates that the configuration is wrong and must be re selected. Otherwise, it will leave behind future problems and cause greater trouble. However, as long as there are many final detection steps, even if the selection is wrong, there is still a chance to make up for it. Therefore, the last step is the key to replace the starting capacitor.