What are the standards for the installation of distribution boxes in Russia?

At present, there is no published detailed standard for the installation of distribution boxes in Russia, but generally speaking, you can refer to IEC standards and relevant Russian electrical safety regulations and building codes. The following are some common requirements:

Installation location and environment

Safe place: it should be installed in a dry, well-ventilated place without inflammable and explosive gas and dust, away from water, steam and corrosive substances, and avoid being installed in a place that is vulnerable to mechanical damage.

Operating space: There should be enough space in front of the distribution box to facilitate operation and maintenance. Generally, there is no obstacle within 0.8-1.2m in front of the box.

Installation height: if it is a floor-mounted distribution box, the bottom should be a certain distance above the ground, usually 50-100 mm; If it is a wall-mounted distribution box, its installation height generally makes the center height of the operating handle about 1.2-1.5m.

Fixation of distribution box

Firm and stable: the distribution box should be installed firmly, horizontally and vertically, and the vertical deviation should not be greater than 3 mm. When concealed, there should be no gap around the distribution box, the edges around its panel should be close to the wall, and the contact part of the box with buildings and structures should be coated with anticorrosive paint.

Fixation method: when the surface-mounted distribution box is installed on the wall, it can be fixed by open-ended bolts (expanding bolts), and the bolt length should be appropriate; For smaller distribution boxes, wooden bricks can also be embedded at the installation place, and then fixed at the wooden bricks with wooden screws. When installing the concealed distribution box embedded in the wall, the reserved hole should be about 20mm larger than the length and width of the distribution box, and the reserved depth should be the thickness of the distribution box plus the thickness of the plaster on the inner wall of the hole. When burying the distribution box, the box body and the wall should be fixed with concrete.

Internal electrical connection and wiring

Selection of wires: The wires with appropriate specifications and materials should be selected according to the rated current and use environment of the distribution box, and the insulation performance of the wires should be good, and they can withstand the expected electrical load.

Wiring specification: The wires in the distribution box should be neatly arranged and firmly bound, and the wires with different phase sequences should be clearly distinguished in color. The connection between wires and electrical components shall be firm and reliable, and there shall be no looseness or virtual connection.

Bus bar setting: Zero line (N line) and protection zero line (PE line) buses shall be set respectively, and the zero line and protection zero line shall be connected on the bus bar, and shall not be spliced and numbered.

Fuse installation: the spiral fuse installed in the distribution box, its power cord should be connected to the terminal of the middle contact, the load line should be connected to the threaded terminal, and the porcelain plug-in fuse should be installed vertically.

Safety protection

Grounding requirements: the shell of the metal shell distribution box must be reliably grounded (connected to zero), and the grounding resistance should meet the requirements of relevant standards to ensure that the current can be safely led into the earth in case of leakage and other faults.

Insulation protection: the electrical components and wires in the distribution box should have good insulation performance to prevent electric shock accidents. When the wire leads out of the panel, the wire hole of the panel should be smooth and burr-free, and the metal panel should be equipped with an insulating protective sleeve.

Protective doors and locks: the distribution box should be equipped with protective doors, which can be closed tightly and locked to prevent irrelevant personnel from touching internal electrical components at will and avoid the danger of electric shock and misoperation.