TECHNICAL SUPPORT
Published 2026-03-24
The most troublesome thing about playing with theservois looking at the three wires of different colors and not knowing where to insert them. If it is plugged in wrongly, theservomay not move at best, or smoke may appear when it clicks, and the board will be scrapped directly. Today we will explain this step by step, along with illustrations and videos, so that you will never have to panic when wiring in the future.
Red line, brown line, orange line, what do they mean? In fact, it is very simple: the red one is the positive pole of the power supply, which is connected to the 5V or 6V power supply; the brown or black one is the ground wire, which is GND; the remaining orange or yellow wire is the signal wire, which is connected to the PWM output port of the control board. Remember this formula of "red for positive signals, brown for negative signals, orange for negative signals", and you will basically not go wrong.
What should I do if I have a second-handservoor the wire is cut? You can use a multimeter to test it: set the meter to the buzzer setting, connect one end to the servo housing (the metal part is usually connected to the ground), and the other end to three wires respectively. The one that can beep is the ground wire. Then use the resistance switch to measure the remaining two wires. The smaller resistance is usually the positive terminal of the power supply, and the remaining is the signal wire.
Many friends think that "if you pick up the wrong one, it's a big deal and you have to change it back." In fact, it's not that simple. Once, I helped a friend debug a robotic arm, and he connected the power cord and the signal line backwards. The moment the power was turned on, the internal chip of the servo burned through, and a burnt smell came out. Not only was the servo scrapped, but the IO port on the control board was also broken.
Even if it is not burned, incorrect connection will cause the servo to not work properly. For example, if the power supply and ground are connected reversely, the servo will rotate in the opposite direction but is weak and prone to heat; if the signal cable is not connected properly, the servo will keep shaking or only turn in one direction. Therefore, be sure to check carefully before wiring. It is best to use terminal blocks or DuPont wire to test first and confirm that it is correct before soldering.
When working on projects, we often encounter situations where the servo is too far away from the control panel and the cable is not long enough. The simplest way is to extend it with a male-to-female DuPont wire, but be aware that the connectors can easily loosen. If it is a fixed installation, it is recommended to use welding and heat-shrinking tubes to weld the extension cord and then put on the heat-shrinking tube for insulation. This is the most reliable.
️ If you want to be more flexible, you can buy ready-made servo extension cables, which are available in 10cm, 30cm, and 50cm specifications. The two ends are male and female, and they can be connected directly in series. Note that too many extension cords will cause voltage drops. It is best to use thicker wires if the length exceeds 1 meter, such as 22AWG silicone wire, to reduce the impact of voltage drop on the steering gear torque.
When making equipment such as robots or multi-axis gimbals, you often face the situation of connecting four or five servos at the same time. At this time, you must not plug the power cords of all servos directly into the control board. The reason is that the 5V output current on the board is generally only a few hundred milliamps. Such a weak current cannot drive multiple servos at all. The correct approach is to connect an external power supply module, like a 5V/5A switching power supply, and connect the red wires of all servos together to the positive pole, and the black wires together for grounding operation.
The signal lines can be connected to different IO ports of the control board respectively. During this process, it should be noted that it is best to control each servo independently. If bus servos are used, only one signal line is needed to connect all the servos in series, and different IDs can be set to distinguish them. This will make the wiring easier.
When powering in parallel, remember to add a large capacitor to the power module, such as a capacitor. Its function is to prevent voltage dips when multiple servos are started at the same time.
Many tutorials often give wiring diagrams, but novices often have trouble understanding the symbols. VCC (power supply positive), GND (ground), and SIG (signal) are generally clearly marked on the wiring diagram, and are also marked with colors next to them. For example, a thick red line represents VCC, black represents GND, and white or yellow represents SIG. Newbies only need to find the corresponding pins on the control board and connect them one by one according to the colors.
For newbies, it is crucial to understand these markings on the wiring diagram. When faced with many complex electronic components and circuits, only by accurately understanding the meaning of each symbol and color can you successfully complete the connection of the equipment. Just like the VCC, GND, SIG mentioned above, and their corresponding color markings, they are key guidelines for connecting to the control board. As long as novices find the pins on the control board according to the color correspondence and connect them correctly, they can gradually build a complete circuit system and realize the normal operation of the equipment.
Please note when looking at the actual diagram: Some servo connectors are 3-pin DuPont connectors, which are directly plugged into the pin headers on the control board; if they are bare wire connectors, you have to solder them yourself. In addition, some servos come with a JST plug, which requires an adapter cable to connect to the DuPont interface. It is recommended to put the wiring diagram and the actual servo together, and match them one by one, so as not to be too troublesome.
When watching video tutorials to learn operations, you must not just follow the steps. You must pay careful attention to the details of the operations. Just like the servo used in the video, you should carefully confirm whether it is consistent with the model of the servo you are using. You should know that the line sequence of servos of different brands is likely to be different, especially the difference between imported servos and domestic servos is more obvious.
In addition, you also have to pay attention to the power supply voltage used by the servo in the video. Normally, 9g servos generally use 5V voltage, while high-torque servos may require 6V or 7.4V voltage. If the power supply voltage is incorrect, the servo will most likely be burned out.
In addition, you should learn the wiring techniques in the video: when inserting the Dupont wire, align it with the gap and do not insert it backwards; when welding, control the temperature of the soldering iron at about 300 degrees to avoid burning the wire. Pause more, compare with more screenshots, practice it again after watching the tutorial, and refer back to it anytime if you encounter any problems. In fact, it is better to read it ten times than to pick it up yourself. Try it boldly and test carefully, and you will be able to get started quickly.
When you were working on a steering gear project, did you ever burn the equipment due to wiring problems? Or do you have any unique wiring tips? Welcome to share your experience in the comment area, and let’s avoid detours together.
Update Time：2026-03-24
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