Power Cable vs. Control Cable: What Is The Difference?
Power and control are some of the most common functions of electrical cables. In this blog, we discover the differences between the two and name the most common types of power and control cables.
What is a Power Cable?
The power cable is the type of cable used to send the energy from its source to the equipment. Power cables are used in overhead and underground energy transmission, as well as in industrial settings. These are multi conductor cables with aluminum or copper conductors.
Types Of Power Cables
Depending on the transmission system, power cables can be AC or DC. AC cables are used in domestic 50 Hz systems, while DC cables are used in DC transmission systems.
Standard power cables include:
- Service entrance cables (aluminum and copper)
- Aluminum mobile home feeder cables
- RHH/RHW-2/USE-2 (aluminum and copper)
- XHHW-2 (aluminum and copper)
- THHN / THWN-2 (aluminum and copper)
- Aluminum URD direct burial cables
- Aluminum service drop cables
- MV-105 cables
- UF-B wire
- NM-B Romex
- Medium voltage power cables
In an industrial setting, popular types of power cables are Type W, Type G, type G-GC, and others.
What is a Control Cable?
Control cables are designed in automation control for sending signals that control the equipment, as well as for measurement and regulation. Due to the nature of the environment they are used in, these cables have to be flexible or flexing.
Control cables are applied in automation systems, transport, building, construction, mining, and industry. These are multi-conductor cables. It is more common for them to have a copper conductor because of its superior conductivity.
Control vs. Instrumentation vs. Signal
The terms control, instrumentation, and signal refer to cables that are not used to transfer power. However, there is a subtle difference between these terms.
Signal cable includes coaxial cables, twisted pair cables, and fiber optic cables. The control wire is similar to signal cables as both carry signals. However, signal cables transmit data. Therefore, they need shielding to prevent electromagnetic interference. A regular control cable does not always have shielding.
Another term commonly related to control cable is instrumentation cable. The cables that fall under this definition also need protection from crosstalk and EMI. Sometimes, the terms "control" and "instrumentation" may be used interchangeably to refer to the same cable. Instrumentation and control are related functions.
Types Of Control Cables
According to the primary classification, VDE Standards, there are three types of control cables: CY, YY, and SY. YY is a regular unshielded cable.
CY is a flexible cable protected from EMI. It is either individually shielded or has an overall shield. SY cables have a steel wire braid for control applications that require extra mechanical protection.
Standard control cables on the market are SEOW control cables, sprinkler control cables, tray control cables, marine control cables, and others.
Differences Between Power and Control Cables
Both power and control cables are used in industrial, residential, and commercial applications. Aside from the overall purpose, power and control cables have many differences.
- For one, they differ when it comes to voltage. Power cables usually have a higher voltage than control wires at 0.6/1kV and higher. Control cables operate at 300/450/600/750V.
- Since power cables are used in an active environment and transfer a high amount of energy, they call for excellent sheathing. In a power cord, the sheathing is strong and sturdy and is resistant to different external factors, including corrosion and temperatures. Control wires do not require the same sheathing and often have regular PVC insulation.
- When used in the same environment, such as industry, a power cable needs a thicker insulation and jacket than a control cable.
- Control cables usually have an elaborate color coding, while power cables are often black and white.
Power Control Cable: Between Two Functions
While the distinction between power and control functions is quite clear, some cables cannot be placed in either of these categories. The reason for this is that they perform both functions. These include airport lighting cables, welding cables, different types of marine and shipboard wires, portable power cords, and others.
