What does alternating current cost

Heavy current connection

The difference between socket and power socket or alternating current connection and power connection

AC connection: A common household uses many electrical devices. Most of the time we need an alternating current connection, which is made available to us via a normal 230 volt socket. A standard 230 volt socket has three connections: 1 phase (black or brown); Neutral conductor (blue) and protective conductor (green yellow). For these 230 volt sockets, 3-core installation cables NYM-J 3 × 1.5 are often laid and protected with a 10A circuit breaker. Thus, this 230 volt socket could be loaded with consumers up to a maximum of 2,300 watts. If a 16 A circuit breaker was used for protection, the socket could be loaded with 3,680 watts.


Power connection: Sometimes this connection is not enough. Then the high-voltage connection is used. In contrast to the 230 volt socket, the high-voltage connection has 3 phases or outer conductor L1, L2, L3 at 400 volts AC. The best example is the electric stove or oven in the kitchen, but also the sauna, or the circular saw, the welding machine in the workshop. Because these devices require a significantly higher performance. thus a 5-wire cable is laid for the power connection. The cross-section of this connection depends on the device for which the connection is used. A NYM-J 5 × 2.5 installation cable is often used for a 400 volt power socket with 16 A.

Three-phase alternating current

The high-voltage connection or three-phase current is a three-phase alternating current, the three individual alternating currents with the same frequency that are fixed to each other by 120 °. Actually, the name “heavy current connection” is not correct, it is just colloquially known as that. Three-phase alternating voltage or three-phase alternating current is correct.

The main task of the three-phase system in electrical engineering is to transport and distribute electrical energy in power grids. The three-phase system is used, for example, for the local power supply in the 230 V / 400 V low-voltage network (single-phase / three-phase). Many electrically operated motors are often operated with three-phase alternating current (high voltage connection).

Compared to an individual single phase With a symmetrical three-phase system, the alternating current system halves the cost of materials for electrical lines with the same electrical power. Furthermore, three-phase AC transformers can be manufactured with a smaller core cross-section than single-phase transformers with the same power. The use of the three-phase system makes economic sense from a few kilowatts and justifies its importance in the field of electrical energy technology (source Wikipedia).

Note: Working on the electrical system can be life-threatening. For legal reasons, I would like to point out that all articles with explanations in writing and pictures are not complete installation instructions for electrical systems. You only get tips, help and suggestions from the point of view of the author and operator of this blog.

Important: In the event of improper and improper execution, no liability will be accepted for personal injury or property damage. The work should therefore be carried out or at least checked by qualified personnel.

A high-voltage connection in private housing

In private housing, for example, a high-voltage connection is used when connecting an electric stove.

A power connection is also often used in your own saunas or a CEE power socket, for example in the workshop, in the basement or in the garage for garden tools, high-pressure cleaners, motors, etc.

How do you connect a power outlet?

CEE sockets are colloquially called “power sockets”. There are sockets with three-phase alternating current (L1, L2, L3), neutral (N) and protective earth (PE). The nominal voltage is 400 volts. The international designation for CEE plugs, couplings and sockets for industrial use has been used since 1999 as IEC 60309 designated.

However, this designation also includes other plug connections which we do not want to go into here.

The CEE standards were tried to unite in Europe, as there are different connector systems. Unfortunately, this attempt did not work and there are many different plugs and sockets in Europe with their own designations and specific standards.

Whoever speaks of CEE plugs usually means those for a high-voltage connection. However, they are also known from the camping sector and especially in industry.

The CEEforce-Sockets are available in sizes 16A, 32A, 63A and 125A. Operating temperatures of -25 ° to + 40 ° are permissible. They all have to have an IP rating of at least IP44.

In many European countries with a 400V three-phase alternating current network, the 5-pin CEE plugs, couplings and sockets in sizes 16A and 32A are used as power connections.

The following designation is noted on the red housing: "3L (P) + N + PE, 6h". “3L” stands for three phases, “N” stands for neutral conductor, “PE” stands for protective conductor. The designation “6H” stands for the arrangement of the protective conductor pin in the round plug. “6H” means the protective conductor is located where the “6” is on the clock, namely at the bottom.

If you open a 16A CEE power socket (3L + N + PE, 6h), you will find 5 connection terminals and a cable gland as strain relief.

Three connection terminals (L1, L2, L3) are for the external conductors (3 phases) of the network, one connection terminal is for the neutral conductor (N) and the protruding, thicker terminal is for the protective conductor (PE).


A fixed cable connection (NYM-J) to a CEE power socket

Using an example, I would like to show you how you can create a permanent high-voltage connection to a CEE power socket 16 A with a NYM-J 5 × 2.5 mm² cable. This is a 5-core, rigid installation cable with a 2.5 mm² core cross-section.

In practice, this connection is used very often. In private residential construction, for example, this connection can be found in garages for garden tools or machines and motors. But also in the basement, for example in the workshop, a power socket 16A is often installed.


The following material and tools are required for the high-voltage connection of a 16A CEE power socket:
  • 1 CEE power socket *
  • A permanently installed power connection with installation cable, for example NYM-J 5 × 2.5 mm²
  • Hammer drill (for concrete or brick wall)
  • Dowels and screws
  • Voltage tester * (do not use a phase tester)
  • different sizes of screwdrivers
  • Wire stripper
  • Side cutter
  • Sharp knife

Step by step instructions:

Power connection of a CEE power socket 16 A.

  1. Open the cover of the power socket with a screwdriver.
  2. Check the absence of voltage using a voltage tester on the existing connection cable and secure it against being switched on again (the cable could be secured).
  3. Important: When working on electrical systems, always observe the 5 safety rules.
  4. Now draw the drill holes with a pencil through the specified height of the power socket.
  5. Carefully drill holes using a hammer drill (for concrete or brick walls).
  6. Fasten the CEE power socket to the wall. The attachment should be very stable, since with power sockets the plugs can only be plugged in or unplugged with considerable effort. Due to the constant load, a very good fastening is essential.
  7. Strip the connection cable with a sharp knife. Allow enough leeway in length for the ladder. Extreme caution is required when stripping the jacket. Very carefully cut into the coat, then bend the coat and peel it off. Under no circumstances damage the insulation of the individual wires, otherwise a short circuit can occur (caution, do not cut into the copper conductor).
  8. Insert the connection cable into the CEE power socket until the jacket protrudes approx. 1 cm into the connection socket.
  9. Strip the wires with a wire stripper (the length should correspond to the length of the terminal point).
  10. The CEE power socket has five connection terminals, namely a protective conductor terminal “PE”, a neutral conductor terminal “N”, and three external conductor terminals L1, L2 and L3.
  11. First the protective conductor (green yellow) to the PE terminal. This is labeled PE. The PE terminal protrudes a little so that in the event of a fault, for example when the cable is pulled out of the socket, the protective conductor is the last to be torn off.
  12. The right tools and feeling are required when connecting the conductors. Make absolutely sure that no insulation is pinched and that the wires are not too loosely but also not too tightly tightened. After each wire connection, it is necessary to check again by pulling briefly.
  13. Next, clamp the blueness Wire (neutral conductor) to terminal “N”.


14. The 3 outer conductors (phases) are labeled L1, L2, and L3 on the connector. Clamp the first outer conductor (brown) to terminal “L1”.

15. The second outer conductor (black) to terminal “L3”.

16. The third outer conductor (Gray) to terminal “L3”.

17. After another visual inspection and check of the conductors, close the housing and sealing screw connection (if present) again. Many CEE power sockets * also have a plastic screw connection, which must then be tightened after connection. Great care must be taken here again in order to fully fulfill the purpose of tightness and strain relief.

18. Functional test! Check with a voltage tester * (it should be suitable up to 400 volts) or with a measuring device. You should also check the spin box. With a new connection there should always be a clockwise rotating field. You can check this with a rotating field measuring device *. With a counterclockwise rotating field, simply swap two outer conductors (phases) when connecting and check again.


Further step-by-step instructions on the subject of “connecting yourself”. Find out more and READ more here.


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Filed Under: Electrical ConnectionsTagged With: Power Connection, Connect Power Socket