The Relationship Between Signal Wires and Power Wires

Signal lines and power lines are two key lines in electronic systems that are interdependent and have clear division of labor. Their relationship can be analyzed from the following five dimensions:

Power Wires:
Purpose: To deliver electrical power to a device, allowing it to function.
Focus: Primarily concerned with voltage drop, heat dissipation, and ensuring a safe and reliable path for the current flow.
Size and Shape: May need to be larger and shaped specifically for high currents and to manage heat.
Examples: Wires in a household circuit or the wires carrying power to a computer.

T4171310005-001 2 x Signal + Power Cable 1.5 mm2 Assembly

Signal Wires:
Purpose:
To transmit electrical signals or data between devices.
Focus:
Concerned with signal integrity, minimizing noise and interference, and ensuring accurate transmission of information.
Shape and Design:
May need to be designed to maintain consistent electrical properties and minimize signal distortion, especially at higher frequencies or longer distances.
1. Functional complementary relationship
‌Signal line‌: carries low-power information transmission, including control signals, analog/digital signals (such as audio, video, sensor data), is sensitive to electromagnetic interference and needs to ensure signal integrity.
‌Power line‌: is designed to provide power for equipment, transmit high-power current (from a few watts to megawatts), and needs to ensure the stability of voltage and current to maintain equipment operation.

signal cable and Differences From Control Cables

2. Physical structure differences
‌Conductor and shielding design‌:
Signal lines often use multi-core twisted wires or coaxial cables, some with metal shielding layers to suppress interference (such as RVVP wires).
Power lines are mainly copper conductors, with simple structures but large cross-sectional areas. Some high-voltage power lines need to pass safety certification.
‌Typical types‌:
Signal lines: twisted pair (anti-interference performance is related to twisting distance), optical fiber (non-metallic carrier).
Power lines: general rubber plastic wire (kestävä), soft power lines (applicable to home appliances).

3. Transmission characteristics and interference protection
‌Voltage/power range‌:
Signal line: The voltage is usually a few volts to tens of volts, and the power is in the milliwatt level.
Power line: The voltage can reach kilovolts, and the power covers watts to megawatts.
‌Anti-interference measures‌:
Signal lines need to be routed away from power lines, and shielding and ground grid isolation are used (such as separation of digital ground and analog ground in PCB).
The power line uses decoupling capacitors (chip capacitors are installed nearby) and wide ground wire design to reduce loop interference.

4. System layout coordination
‌PCB design rules‌:
The power line and the ground line form a closed loop to avoid cross routing; the digital circuit adopts a “well”-shaped ground grid layout.
The signal line follows the shortest path principle, and the sensitive signal area avoids overlapping with the power layer.
‌Connector adaptation‌:
In mixed transmission scenarios, multi-functional connectors that are compatible with signals and power should be selected to reduce the number of interfaces.

5. Interchangeability under limited conditions
In certain scenarios, signal lines can temporarily replace power lines through technical transformation, for example:
‌POE power supply‌: Ethernet twisted pair cables transmit data and power at the same time, but are limited by power and distance.
‌Adding an adapter‌: Esimerkiksi, video signal cables need to be powered by twisted pair transmitters.
However, in conventional applications, the two are not interchangeable due to differences in carrying capacity and anti-interference requirements.

Copper core power cable, signal control cable rvv12 core 14 ydin

The wiring harness consists of two elements: wires (signal wires, power wires) and connectors.
In addition to electronic components, wire harnesses are also indispensable in electronic products. Although many products use board-to-board connectors in place of wires, most electronic devices still cannot be separated from wire harnesses in terms of signal and power transmission. A wire harness usually consists of wires, connectors, jacketing, or insulation. The editor of YAXUN Electronic Connectors will discuss with you the role relationship between signal lines, power lines and connectors in the wiring harness.

As the name suggests, signal lines mainly refer to the lines used to transmit sensing information and control information in electrical control circuits. Signal lines usually consist of multiple cables forming one or more transmission lines, or they can also be printed circuits arranged in a printed circuit board. With the continuous advancement of science, technology and applications, signal lines have developed from metal carriers to other carriers, such as optical cables. In order to facilitate standardized production and application, signal lines for different purposes usually have different industry standards.

Power lines are wires that carry electrical current. Typically, point-to-point is how electricity is transmitted. Power cords can be divided into DC power cords and AC power cords according to their uses. Generally, AC power lines are wires that pass high-voltage alternating current. Due to the high voltage, this type of wire cannot be officially produced until it obtains safety certification according to unified standards. DC DC lines basically pass through a lower voltage DC power supply, so the safety requirements are not as strict as AC AC lines. However, for security reasons, countries still need unified security certification.

The big difference between signal lines and power lines is that signal lines transmit analog signals or digital signals, and power lines are used to transmit current. Signal lines refer to lines that transmit data, and power lines refer to circuits that provide power. In fact, electrical signals also run in signal lines, which are just regular, arranged, and information-carrying electrical signals. The power cord only carries DC current with a fixed voltage value. In electronic equipment, connectors function without causing signal absorption, attenuation, and power loss to system performance. It also provides detachable connection devices between electronic systems. Siksi, a wire is needed to connect between them.

Signal lines, power lines, and connectors can exist independently or coexist. If there are signal and power transmission requirements in electronic products, how can there be fewer connectors? Siksi, these three are interdependent and coexisting, and are indispensable in electronic products.

The above is what the editor shared, I hope it will be helpful to everyone. YAXUN Electronics provides integrated R&D and production services from the development of plastic and hardware terminal molds for products, to precision plastic injection molding, high-speed stamping of precision hardware terminals, terminal plating, and automated assembly of wire harnesses. If you need more detailed information, you can contact the staff for consultation.