Search term
0
Search term
0
United States
 
 
United States
 
 

Direct current for an efficient factory of tomorrow

Knowledge about DC and suitable cables


It has become clear that the power supply to industrial factory floors will increasingly be established via direct current in the future. By deviating from the previous AC supply, a higher energy efficiency and many other advantages can be achieved in an increasing number of applications that already internally rely on DC intermediate circuits. Companies can also reduce their CO2 emissions.

What benefits and opportunities does a DC supply system offer?

In the following text, you will find an overview of the objectives of factories supplied with direct current. Cables and wires are essential components when planning the construction of such infrastructure. We can, of course, supply you with our range of DC cables for the low-voltage range, which is perfectly tailored to industrial requirements.

White paper "Cable cross-section calculation for direct current"

Our DC experts have created a guide that can assist you in calculating and selecting the cross-section for cables in AC and DC systems. Ask yourself:

  • Which formulas can be used to calculate the conductor current for a DC grid?
  • How do you determine the required conductor cross-section?
  • How do you take the expected cable length into account in your calculations?

To get answers to these and other questions, download our white paper.

Download the free LAPP whitepaper

LAPP is a founding member of the ODCA


LAPP has been actively involved in research projects on the topic of direct current in industry for years and joined the newly formed ODCA (Open Direct Current Alliance) in 2022 as a founding member. ODCA is considered a successor project to DC-INDUSTRIE2. The focus is now on the benefits of supplying industrial energy grids with direct current and the necessary international standardization of existing concepts. Direct current is a promising lever to support a successful energy transition and thus an important contribution to climate and resource protection.

Flyer: Direct Current

Industrial DC power supply for production plants - with the world's first DC cable portfolio from LAPP
Download it now

White paper

Calculation and selection of the cross-section for cables in AC and DC systems
Download the free LAPP whitepaper

White paper

Comparison of copper cross section and transmission losses for cables in AC and DC systems
Download the free LAPP whitepaper

Objectives of an industrial supply network with direct current


Implementing energy transition and reducing CO2 emissions

The idea of converting industrial production plants to direct current is not new, but rather the result of successfully implemented DC projects, such as DC-INDUSTRIE and DC-INDUSTRIE2, in which industry and research are working on implementing energy transition in industrial production. The concept of sustainability plays an important role here. This is because electric motors and drives are by far the biggest reasons for energy consumption in industrial production. If their energy requirements could be reduced or their efficiency increased, this would have a direct impact on a company's CO2 emissions.

Greater flexibility and supply stability through the integration of renewable energies

DC grids are also promising because, compared to AC grids, they offer greater flexibility while providing greater stability. When renewable energies are integrated, highly automated and digitally networked production environments benefit from a centralized and autonomous power supply and permanently stable plant availability.

Large-scale involvement within the industry will speed up standardization for DC systems. Through close collaboration between users, planners, manufacturers, suppliers, research institutes, standardization organizations and associations, the hope is to accelerate the transition of the industrial power supply.

When and for whom is direct current an option?


Anyone constructing a new plant today should explore the topic of power supply through direct current.

Which production plants are suitable for a DC system?

  • Plants with high power requirements, e.g. arc or welding applications
  • Factories that generate electricity on site using renewable energy
  • Plants that precisely control, position, accelerate and brake devices and machines using a variety of servo motors and drives
  • Plants with robotics applications in which dynamic movements are performed
  • Large office buildings

Whether it's plant and mechanical engineering, data centers, logistics or renewable energies – DC grids are making their way into many industries. We will provide you with information about the benefits of supplying plants with direct current.

Reviewing the transformation process.

Understanding alternating current and direct current


What do the abbreviations AC/DC refer to? In electrical engineering, these abbreviations have always stood for the two types of current: alternating current (AC) and direct current (DC).

What are alternating current and alternating voltage?


Most classic machines or household appliances operate using alternating current. An alternating current is a current that constantly changes its direction of flow.


An alternating voltage is generated in large power station generators (e.g. in water, coal or nuclear power stations). This is an electrical, sinusoidal voltage with periodically changing polarity. If consumers (in the grid) are connected, a sinusoidal current flows.


In addition to systems with a single-phase alternating voltage, there are also three-phase current systems. Instead of just one, there are three current-carrying conductors with 120° phase-shifted alternating voltages to be able to supply electricity to large machines and devices that require more power.

What are direct current and direct voltage?


Computers, mobile phones and even LEDs work with direct current. A direct current is a current that does not change its direction of flow.


A direct current is only generated when a direct voltage is present. This is an electrical voltage which always has the same polarity.

5 solid reasons to use direct current in your factory floor


Switching industrial production plants from alternating current to direct current offers several advantages:

Direct current supply: what savings can you expect?


The DC supply has many benefits, but also various cost savings, which could allow installation expenses to be amortized over time.

Energy savings through

  • Integration of storage systems
  • Integration of renewable energies
  • Use of all recuperation energy
  • Fewer transmission losses

Resource savings through

  • Cables with smaller cross-sections and fewer conductors (low copper requirement)
  • Fewer converters, smaller converters (means more space)

Protection against plant downtime caused by external grid fluctuations

  • Costly downtime in the production process and high repair costs are avoided.

What is the difference between DC and AC cables?


At LAPP, we are the global market leader in the field of cable and connection technology and are experts in the properties of cables for the low-voltage range. Here is our overview:

Differences in design

5-conductor cables are required for power transmission with alternating voltage (three-phase current system); in the case of direct voltage, 1 or 2 fewer conductors are required. A DC cable consists of a DC+ and DC- conductor and, in the simplest case, a neutral conductor.

Differences in colour coding

The conductors of a cable designed for direct current are color-coded differently from alternating current cables. According to DIN EN 60445, the outer conductors of DC cables must be identified in red and white, and the outer conductors of AC cables are coded in gray, brown and black.

Material use

Due to a lower number of conductors and smaller conductor cross-sections, less copper is usually required for DC cables than for AC cables. Attention must be paid to high-quality conductor insulation for the intact DC voltage supply in line with the relevant circumstances. However, there are no additional specifications in this regard compared to use with alternating voltage.

Choice of conductor cross-section

By choosing the correct conductor cross-section, cables are dimensioned to the required current rating. With the associated protective elements, the connected devices are protected against overload and short circuits. In many cases, the same process as for AC cables can be used to determine the required cross-section. Determine the conductor current, take the installation type and cable length into account, and check whether the cable material used is suitable for its temperature resistance.

Cables and wires from LAPP for a full-fledged DC grid


At LAPP, we have been researching the long-term stability of insulation materials for cables and the insulation strength of conductor insulation for decades. We are now also a pioneer in the development of low-voltage cables for industrial and other DC applications.

Fig.: Example depiction of a factory floor with a direct current supply

We understand your challenges and have a high-quality, state-of-the-art portfolio geared towards direct current with the essential components for a DC grid.