Electrical cables and wires are an essential part of any installation. They differ in their purpose and technical specifications. One of the main divisions concerns cables designed for alternating current (AC) and direct current (DC). In the following article, we will present what these terms mean, what they mean in the context of electrical cables and wires, and discuss the basic differences between alternating current and direct current. This knowledge will help us decide when to use specific types of cables and how to choose the right solution for our needs.
Check the cables and electrical wires at the Onninen wholesaler
What does the notation AC mean for electric cables?
First, we should understand the markings on the cables, which will help us notice the differences between them. The notation "AC" is an abbreviation for the English expression Alternating Current, or alternating current. It is therefore designed, as its name suggests, to work with alternating current, one that changes the direction of flow in a cyclical manner. In electrical installations powered by such current, the voltage is subject to constant changes, which is why it reaches positive and negative values with respect to the zero point. This type of cable is commonly used in domestic, commercial and industrial installations. This is because alternating current is the dominant type of electrical energy in power grids around the world.
AC cables and wires must be designed to withstand voltage fluctuations, ensuring safe and uninterrupted power transmission at different current values. Depending on the specific application of the wire, it can have different diameters and insulation layers to protect against overheating and the risk of damage. In electrical installations found in homes, we most often deal with a voltage of 230 V. This is the standard power supply value for most electrical devices. However, when it comes to larger industrial systems exposed to long-term current load, higher voltages are used. This requires the appropriate selection of AC cables with higher resistance.
Installation cables are also exposed to another threat here, because in the case of alternating current, magnetic induction occurs. It is therefore important that their design is able to minimize electromagnetic interference. For this reason, special shielding of AC cables is used, which prevents the influence of electromagnetic fields on other devices in the vicinity. This must also be remembered when designing such a system.
What does DC mean in electrical wires and cables?
Now let's move on to the designation "DC", which stands for Direct Current. It occurs on cables designed to transmit direct current. Unlike alternating current, the current flows in only one direction. DC cables are commonly used in power supply systems for devices such as photovoltaic systems, batteries or electric cars. They should be designed to meet the specifics of direct current. It is characterized by a stable flow of energy, so the requirements for insulation, as well as mechanical resistance, are different than in the case of AC cables.
Electrical installations based on direct current have a different specificity, the voltage is often lower here than in systems with alternating current. However, this does not mean that designing them is easier. Such cables are used, for example, in photovoltaic systems, where solar panels are connected to the inverter by a DC cable. The selection of cables is therefore crucial for the optimal operation of the entire installation, as well as its safety.
Another challenge in DC installations is the need to eliminate energy losses. Direct current is such that, especially over longer distances, it can cause greater energy losses compared to alternating current. Insulated cables of the appropriate diameter are therefore key here to minimize these losses as much as possible. It must also be borne in mind that DC cables can be susceptible to overheating, which requires their construction to be highly resistant to temperature changes, especially in industrial applications or under heavy loads.
What is the difference in direct and alternating current flow?
Knowing what the wire markings are and their characteristics, we can move on, focusing on the differences that occur here. These have already been described in some way in the previous paragraphs, but now we will gather the most important things in one place.
We can therefore say that the main difference between direct current (DC) and alternating current (AC) is the way in which energy flows through the wire. In alternating current, this direction can change cyclically, making transmission more efficient, and over long distances. This is particularly important in large networks, where power cables can transmit energy without interference. This means that changes in the direction of the current can occur here dozens or even hundreds of times per second (depending, of course, on the voltage frequency).
Direct current, just as its name suggests, is characterized by a constant flow direction, which makes it more stable, but at the same time less efficient when transmitted over longer distances. It is no coincidence that DC is often used in devices that require precise and stable power supply, such as electronics. Direct current also does not generate energy losses associated with electromagnetic induction.
Another difference is the way energy is transmitted in power systems. Alternating current is easier to transport at higher and lower voltages. Direct current, on the other hand, requires special converters to be transmitted over long distances. This is associated with higher installation costs.
We can see that both types of current have their own specificity, and the choice between one and the other depends on the specific requirements related to parameters such as installation, transmission distance and the type of powered devices.
Check the cables and electrical wires at the Onninen wholesaler