Power distribution cabinet, purpose and main characteristics

To accommodate receivers and other equipment, a power distribution cabinet is installed, installed at production sites, residential buildings and power plants. This design allows you to solve many important problems, but only if the cabinet model is selected correctly.

Purpose and features

Cabinets for the installation of power equipment can solve different problems, which depends on their execution. The main function is the reception and distribution of power supply, providing protection against short circuits of power consumers in the event of a sharp increase in voltage in the network.

The operation of the equipment is carried out with:

current of variable or constant value;
voltage indicators 380 V or 220 V;
frequency response ranges from 50 Hz to 60 Hz.

Power distribution cabinet structurally consists of three parts:

metal case - the form can be made square or rectangular, the structural dimensions can also be set different, depending on what equipment will be installed inside. Cabinets designed to solve special production problems usually have large dimensions;
fastenings for power receivers and power distributors. Inside are installed machines, voltage stabilizers, devices for metering and control of reception, as well as the distribution of electricity, voltmeters, fuses, ammeters, and other devices provided for by the design;
fasteners for mounting DIN rails, cable ducts, pipes and other equipment.

The distribution cabinet is also made with a technological hole for pulling the cable inside the case. The diameter of the hole is provided for wiring with the aim of connecting to electrical appliances that distribute incoming electric current. In the simplest designs for laying cables and securing terminal blocks, several DIN rails or ducts are installed.

Kinds

Power cabinets are divided according to several criteria.

Name of criteria	Description	Functions Performed
Number of functions performed	Equipment designed for a narrow task profile	Installation is made on heating systems
Number of functions performed	Multifunctional	Switchboards are used to power machine equipment
On installation	Floor	Mounted on a solid horizontal base
	Mounted	With technological holes provided for securing on a vertical plane
	Recessed	Typically, these cabinets are custom-made and designed specifically to place the intended equipment in openings, niches or other grooves in the walls
* Providing ease of maintenance	Internal installation	For buildings,
* Providing ease of maintenance	Outdoor installation	The distribution cabinet is selected based on the climatic design. Installation is done outdoors
Design classification	Complex points: apartment, floor and lighting	They are used for reception, transmission and distribution of energy in residential buildings.
	Low voltage cabinets	Selected for industrial purposes.
	Uninterruptible Power Supply	In the event of an emergency or emergency due to the development of accidents
	Distribution cabinet operating from two independent power sources	Widely used to solve critical production tasks.
	Multifunctional equipment	With the help of it, reception, metering, energy distribution and protection from possible emergency situations are simultaneously carried out

* In both cases, the protection of the housing element is required. This parameter makes it easy to determine acceptable performance.

There is a development of unique power equipment - an optical switchboard. It can be used to connect fixed and optical cables. One-piece connections are made in the form of plates.

Recessed

Mounted

Floor

Dimensions and specifications

Power distribution cabinets ШРС-1 and distribution cabinets ШР are designed to receive and further distribute current of variable frequencies with a maximum value of 50 Hz. Work is carried out at a nominal voltage rating of up to 380 V and an electron flux of up to 400 A. The protection of the discharge lines is carried out using fuses. Cables at the inlet and outlet can be placed above or below. Performance indicators are given in the table.

Value	Value
Operating Voltage Rating	380 V
Frequency response, nominal	50 to 60 Hz
Insulation Voltage Rating	660 V
Current power characteristic	200A, 250A, 400A
Fuse Current Rating	63A, 100A, 250A, 400A
Number of fuses for installation on feeders	5 or 8 pieces
Execution by state standards	IP54
Climatic modification and category of placement	Ultrasound; U2; UHL
Environmental Group	M3

Overall dimensions produced by the manufacturer 700 * 350 * 1600 mm or 500 * 300 * 1600mm (where 1 values indicate the parameters of width, depth and height). The outdoor distribution cabinet operates at a temperature range from -45 to +40 0С, relative humidity not higher than 80% at + 150С. Operating conditions: no danger of explosions and conductivity, elimination of gas contamination by aggressive substances. Location on the working surface - vertically with a deviation of not more than 50 from a given position. Outdoor distribution cabinet (SHRN) is installed on the areas of production sites or near residential buildings.

Selection rules

Distribution cabinets are recommended to be selected taking into account complex requirements:

by type - the main purpose and requirements for the equipment of the energy supply system are taken into account;
by type of installation - installation is carried out on a solid foundation, with fastening on a vertical plane or built into the intended structure;
according to the specified parameters of the current (voltage, short circuit current or rated current);
according to the degree of protection chosen on the basis of operation in the expected climatic conditions;
on climatic modification.

The outdoor distribution cabinet also has mechanical protection and can be used in areas with a risk of seismic activity. The cabinet of complete switchgears is selected by the consumer, taking into account the place of its installation and execution.

It is recommended to choose a distribution hinged shield, based on the design decision, which should include:

knife switches;
number of outlets;
switches and devices for lighting;
food for electrical appliances;
cable lines.

The number of distribution wall cabinets is selected based on the summarized load indicator. In order to protect electrical wires from short circuit currents, automatic machines are used to switch to rated current.

The telephone cabinet should be selected for capacity, based on the number of cables placed in it. The main criterion for choosing is its height, measured in units. For telephone cables you can choose: wall mounted or floor-mounted distribution cabinet. The latter are available in depths of 600, 800 or 1000 mm. If you need to install an uninterruptible power supply, you should choose equipment with a depth of 800 to 1000 mm, and with the proposed installation of a PBX or switch, 600 mm can be dispensed with. For wall cabinets, the specified depth is 450, 500 or 540 mm.