This picture shows the internal boards of 4-motor control box developed by Jingshi Technology company. As you can see, there are 4 ports on the right side of each board, which can connect and control 4 electric columns at the same time. After shelling, they can be put into use.
The 4-motor control box can be divided into two kinds: high-voltage control box and low- voltage control box, catering to different demands of clients.
