Power supply of office premises

Power supply.

According to the degree of reliability of power supply, the electric receivers of office premises belong to category III. The I category includes fire alarms, security systems.

Power supply of office premises is provided from the building GRF according to the III category of reliability of power supply from one input, supply voltage 3NPE, TNCS with operating voltage 400/230V, 50Hz. The cable from the building GRF to the office premises is laid in the basement of the building.

For power supply of all consumers on the ground floor there is a switchgear control board. With power metering unit installed in it.

Power distribution of lighting and socket networks of rooms is carried out through the RB panel.

Power supply of process consumers, such as the server, ventilation system, is performed by separate groups from individual switchboards of the switchgear in the room with servene and SChC in the ventilation chamber.

Distribution power boards have plastic cases with doors locking to the wrench, are equipped with input control devices and circuit breakers on outgoing lines. Each power distribution board has backup circuit breakers for outgoing lines at the rate of 15% of the number of circuit breakers for outgoing lines (but not less than 2 pcs). Circuit breakers on outgoing lines in boards shall have nominal characteristics in accordance with the calculation.

Panels and electric receivers are connected to each other by communication routes, where cables will be laid.

The design provides for automatic disconnection of the thermal curtain in case of fire. Ventilation disconnection in case of fire is performed in the control panel of air conditioning system ventilation.

Electricity accounting.

The electric power metering device is installed in the control and distribution board of the office premises.

Distribution and group networks.

The entire power distribution system for all offices and grounding from the switchboard of the switchboard is made according to TNS - 380/220V system, 3 phases, zero working (N) and zero protective (PE) conductors.

Group networks are made by WBGngLS cable according to three-wire circuit: phase, zero working, zero protective conductors. Sections of conductors of the group and distribution network are indicated on single-line diagrams of boards.

Mark all power cables with a tag indicating the cable address and brand.

Use conductors in the following colors to route networks:

Black, brown, white - phase conductor;

Blue - to indicate zero operating conductor;

Two-color green-yellow combination - to indicate protective

conductor.

Electrical Load Calculation, Cable Section Selection, Tag Selection, and

parameters of electrical equipment are made in accordance with PUE, SP 31110 and other valid regulatory documents. Power supply and distribution networks of office premises are made with cables with copper cores that do not spread combustion. Networks are protected against overloads and short circuits by the relationship between the currents of protective devices and the capacity of cables.

For consumers of the 1st category, devices are provided without interrupting power supply.

Electric lighting.

The following types of lighting are used in office premises:

- working;

- emergency;

- evacuation;

As part of the working lighting, on-call lighting is provided in the corridor areas to ensure the operation of night safety systems in these zones.

Lighting is controlled from the security post and locally (from switches) in the rooms and corridors.

Emergency lighting required to continue operation is performed through the RB panel in accordance with the applicable codes and regulations .

In rooms with suspended ceilings of the Grillato type, embedded fluorescent lamps are installed. Optical part - screening grid is made of mirror aluminum.

The calculation plane is at the level of 0.85 m. Calculation of illumination indicators is carried out automatically using PC.

Emergency lighting fixtures are equipped with emergency power supply unit. Block

emergency power supply is designed to ensure uninterrupted lighting of premises in case of unexpected disconnection of the network. The unit is integrated into a luminaire with fluorescent lamps with a capacity of 18W and provides emergency operation of one lamp in the luminaire. The duration of lighting is at least one hour. The illumination level is sufficient for orientation, evacuation from the room .

Evacuation lighting with "EXIT" light indicators is made in accordance with SNiP 230595 and Chapter 6.1 of PUE. Indicators are installed above all doors of exits from the building and for corridors. "OUTPUT" lamps are equipped with accumulators ensuring autonomy of operation for at least 1 hour.

Lighting standards are adopted according to MGSN 2.0699 "Natural, artificial and combined lighting."

The degree of protection of the lamps is selected in accordance with the operating environment. Lighting is performed by lamps with fluorescent lamps.

Socket networks.

The layout of the socket groups on the plans was made on the basis of the design project. The project provides sockets for workplaces in offices, for harvesting mechanisms in corridors.

All 220V sockets have a third ground contact.

The sockets shall be installed at a height of 0.2m from the level of the clean floor unless another height is specified.

LAYING OF CABLE NETWORKS.

Cable launches of group networks to sockets and switches are performed concealed in flexible corrugated PVC pipes in wall bars, or in plastic cable channels along partitions.

Cables behind suspended ceilings made of non-combustible materials are laid in metal trays and corrugated PVC pipes.

Cabling shall be laid in such a way that the overall building characteristics and fire safety of the building are not reduced. Openings in the structures of the building through which the cable passes must be sealed with non-combustible, easily removable mastic, so that the required fire resistance of building structures is not reduced.

All posting must be changeable.

Joint laying of mutually redundant supply and distribution lines, electrical receivers of security, fire alarm, in one pipe is not allowed.

Cable laying of group lines of working lighting with group lines of emergency lighting is not allowed.

Install the mounting boxes in the places available for maintenance .

Hidden changeable wiring is made to the places where switches and sockets are installed in the walls.

Potential equalization system.

According to Chapter 7.1 "Electrical Installations of Residential, Public, Administrative and Household Buildings" of the PUE of the 7th edition, paragraph 7.1.87, a potential equalization system is carried out at the input.

Each electrical installation of the building shall have a main potential equalization system connecting the following conductive parts:

protective conductor (PE-conductor or PENconductor) of the supply line; a ground conductor connected to the artificial ground conductor; metal pipes of utilities included in the building (pipes of hot and cold water supply, sewerage, heating, gas supply, etc.); metal frame of the building;

metal parts of centralized ventilation and air conditioning systems. In the presence of decentralized ventilation and air conditioning systems, metal ducts should be connected to the PE bus of the air conditioners and fans power cabinets; grounding conductor of functional (working) grounding, if such is available and if there are no restrictions on connection of functional grounding circuits to the grounding device of protective grounding.

The connection of said conductive parts to each other shall be made by means of a main grounding bus (clamp).

The main grounding bus is made inside the switchgear board.

Copper busbar PE is used as the main grounding bus. The bus structure provides for the possibility of individual disconnection and conductors connected to it. When making the main grounding bus, its conductivity must be at least the conductivity of the PENconductor of the supply line.

All contact connections in the main potential equalization system shall comply with the requirements of GOST 10434 for contact connections of class 2.

The main grounding bus at both ends shall be indicated by longitudinal or transverse strips of yellow-green colour of the same width. Isolated potential equalization conductors shall have insulation indicated by yellow-green stripes. Bare conductors of the potential equalization system at the points of their connection to the third-party conductive parts must be indicated by yellow-green stripes made with paint or adhesive two-color tape.

Protecting people from electric shock.

To protect people from electric shock in case of insulation damage, the following protective measures are performed:

1. grounding;

2. potential equalization system by grounding all metal

pipelines and other similar equipment that may be

under voltage in case of electrical equipment insulation damage;

3. protective disconnection devices in accordance with item 7.1.79 of PUE (published in 1999);

All enclosures, equipment, external electrically conductive parts, metal conduits, troughs and trays, as well as other metal elements, except normally energized, forming protection for electrical equipment, including devices and instruments, must be reliably connected by earthing bridges, for which separate conductors and special grounding clamps are used. The impedance of the protective conductor system shall be such as to provide sufficient current for the protection and opening of the peripheral circuits:

sockets for 0.4 sec.

stationary equipment for 5.0 sec.

Installation Instructions

Installation of electrical equipment shall be performed in accordance with PUE and SniP 3.05.06-85

During installation works, safety precautions shall be provided in accordance with SNiP III480 and the "Safety Regulations for Electrical Installation and Commissioning Works."

The height of the switches installation is 0.9 m from the clean floor, the height of the sockets installation is 0.2 m from the clean floor, unless another height is indicated on the plans. Switches near the door are installed on the wall on the side of the door handle at a distance of 150 mm from the door opening .

The remaining dimensions of electrical consumers references should be specified according to the design design.

Measures for the rational use and saving of electricity

Daily highs in the Mosenergo system fall on 810 and 2023 hours.

At the specified time, the consumer is obliged to reduce the maximum load.

In addition, the following organizational measures must be performed on the objects:

Display posters "Go out and extinguish the light," "Finish work and go to lunch, turn off power" etc.

Appoint a person responsible for compliance with organizational technical measures to save electricity and reduce loads during peak hours by order.

Environmental protection.

The project was developed taking into account the requirements of the legislation on nature protection.

Now about 19% of electricity consumed around the world comes from artificial lighting. The use of fluorescent lamps, which consume 60% less electricity than conventional incandescent lamps, significantly reduce CO2 emissions, which contribute to the greenhouse effect.