A complete hydraulic solenoid includes solenoid coil and solenoid tube assembly. The two parts can be sold both integrated and separately. As the main part of hydraulic solenoids, solenoid coils have a strong impact on hydraulic solenoid performance. In the following article, we will discuss some basic information when choosing a solenoid coil.
Solenoid Coil Detection
When you are choosing a solenoid coil, the first thing you have to check is the solenoid coil detection, and then you can get some basic knowledge about the solenoid coil quality, also the advantages and disadvantages of solenoid coils.
Normally, we have to check the inductance value and the quality factor Q of solenoid coil, to inspect solenoid coil accurately, it needs special instruments, and the measurement method is complicated. In actual working experience, solenoid valve manufacturers do not have to run such test, only examine the continuity checks and judge the size of the solenoid coil quality factor Q. You can use the omh band of the multimeter to measure the direct current resistance of solenoid coil, and then, you can compare the examined solenoid coil resistance with the rated resistance. If the examined resistance is much larger than rated resistance, or the indicator does not move, then it means that the solenoid coil copper wire is broken. If the examined resistance is too small, it means there is a short circuit problem. Both of the two circumstances means the solenoid coil is broken. Only when the examined resistance is similar to the rated resistance, the solenoid coil is in good condition.
The quality factor of solenoid coil can be determined under the following circumstances:
If the inductance value of different solenoid coils is the same, the solenoid coil with smaller dc resistance has the higher quality factor.
If the copper wires have a larger diameter, then the solenoid coil has the higher quality factor.
If the solenoid coil adopts the multi-wires winding method, then the solenoid coil with a larger number of strands has the higher quality factor.
Moreover, the materials of solenoid coil bobbin and solenoid iron core materials can also affect solenoid coil quality factor. If the loss of solenoid bobbin and iron core material is small, then the solenoid coil quality factor is large. For example, the solenoid with iron core made of high silicon electrical steel has larger quality factor than the solenoid with iron core made of ordinary silicon steel.
Notice of Solenoid Coil Winding
In actual solenoid coil winding process, there are a large number of solenoid coils are nonstandard parts. Therefore, during the solenoid coil winding, you must pay attention to the following points:
Choose the solenoid coil winding method based on different circuit needs. When you are winding a solenoid coil, the winding method must be determined by the circuit requirement, inductance value and the diameter of solenoid coil bobbins.
In order to keep the solenoid coil carrying capacity and the mechanical strength, you must choose proper copper wires. The diameter of solenoid coil copper wire can not be too fine. Fine copper wire will increase the solenoid coil resistance, so the solenoid coil quality factor is decreased. Moreover, if the copper wire is too fine, the carrying capacity and mechanical strength of solenoid coil are both small, which makes the solenoid coil easy to burn out.
How to Increase the Quality Factor of Solenoid Coil
Quality factor is the major parameter which shows the solenoid coil quality. Improve the quality factor of solenoid coil is an important way to enhance the solenoid coil serve life.
The Operating Frequency
The solenoid coils used in low frequency stage normally wind with insulated copper wires, such as the varnished wire. If the operating frequency is between 10KHz and 2MHz, the solenoid coil is winded with multiple strands copper wire, In that way, it can significantly increase the surface area of the copper wires, and the quality factor of the solenoid coils will increase 30%-50%. In the circuit with operating frequency higher than 2MHz, the solenoid coil should be winded with heavy copper wires with the diameter of 0.3mm-1.5mm.
High Quality Solenoid Coil Bobbin
Solenoid coil bobbin can also effect the quality factor of complete solenoid coils. Poor quality solenoid coil bobbin materials will increase the medium loss. Use high quality solenoid coil bobbins can decrease the medium loss.
Large Solenoid Coil Diameter
During the solenoid coil design process, we can choose a larger diameter of solenoid coils properly. If the solenoid coil diameter is larger, the volume of solenoid coils is larger, and it can help reduce the loss of solenoid coils. In that case, the quality factor of solenoid coil increases.
