When constructing buildings, it is important to take care of the electrification of the construction site in advance. Without the help of electrical appliances, building is impossible. All necessary tools - drills, concrete mixers, punchers, welding machines - are powered by electricity. Creating a full-time electrification is not always possible, so they use temporary power supply. It is used both in the construction of residential (multi-unit or private) houses, and for the construction of non-residential objects.
Basic power requirements
Since electricity carries a potential danger to builders, the site must meet a number of criteria, without which it is forbidden to make temporary power supply.
- Reliability. Supply must be uninterrupted during the whole construction period.
- Quality. The power supply parameters must comply with the standards and guarantee the stable operation of electrical appliances.
- Safety. All personnel must be protected from electric shock, and the system itself must be made of high-quality reliable components.
After checking compliance with all safety conditions, temporary electricity can be carried out.
Temporary electricity to the site
Summing up temporary power supply to the site is associated with a number of organizational issues. Connection is made to existing highways. Depending on the location of the site, the best method of temporary power supply is selected. The choice depends on the following criteria:
- range of the nearest power line;
- type of object;
- required power;
- kind of network.
If connected to an existing power supply network, contact your sales organization to find out the connection procedure and other conditions. For a standalone generator, permission is not required. How much all the work on temporary energy supply will cost and how much time will be required depends on the chosen scheme.
Features of connection to existing power networks
If the construction site is located next to its own housing, electrification will be the least expensive. During construction, energy that is already available at the facility will be consumed. Payment will be made according to a previously concluded contract with a service provider. In the case of the construction of new facilities, re-registration with a company supplying electricity will be required. To do this, you will need to do the following:
- To write an application.
- Indicate the estimated power consumption and approximate period of use.
- Create an estimate.
- Get technical specifications from the organization and select a connection point for input.
- Order design documentation.
- Coordinate the project with state technical supervision.
- Perform electrical work.
- Call an expert to evaluate and draw up the test report. The act is signed in duplicate - one remains with the applicant, the second with the organization.
- Conclude an agreement with the energy sales organization, sign the necessary documents.
- Hand over the facility.
The application is written in a strictly regulated form. A sample can be obtained from the sales company. You can submit the necessary documents in person or by registered mail or via the Internet.
If the nearest power line is far away, cabling may be required. To fulfill it, you should contact the organization involved in the supply of electricity, write a request for a technological connection and obtain technical specifications. After that, all the stated conditions must be fulfilled and contact the company again to connect and seal the meter.
At the input, it is necessary to connect a shield for temporary connection to electric networks as for constant power supply. For this, a shield with anti-vandal protection and IP54 class is installed. Its dimensions should be such that it is possible to install a meter, protective devices and grounding buses. You should also find a place to install a backup power supply.
Power supply from the generator
An autonomous generator is a source of stable energy supply to the construction site. Its installation does not require coordination and connection to power lines, as well as the cost of wiring cables to a power source. The only drawback is the high cost of equipment. Usually, generators are used at the first stage of construction, while the design and connection of temporary power supply takes place.
Technical Activities
When all organizational issues have been resolved, you can move on to locating the entry shield. If the site is located further than 25 meters from the power transmission line, installation of another additional support is required according to the requirements of the PUE. According to the rules, the shield should be installed on the border or on the territory of the applicant. Cables and supports are removed from the shield to the construction sites.
Wiring diagrams
Temporary connection to power grids during the construction period is accompanied by the appearance of new cable routes of a certain brand and length. All these data should be reflected on the diagram before they are laid. There are several types of connection schemes - radial, ring, mixed wiring.
Radial design is distinguished by power from a single input machine, from which electricity is supplied through cables to power plants and lighting devices. If there is a generator, a ring or mixed circuit is selected.
The radial temporary power supply circuit is duplicated by the connection from the generator, therefore, in case of problems with the power supply of the unit, it can be powered from an autonomous device.
Input design
With self-assembly of the shield, a number of requirements must be observed. All protective devices, energy metering devices should be placed in sealed packaging, which will protect them from moisture and dust. Also, grounding of the shield and zero from the high-voltage power line, as required by the PUE, is necessarily organized. All safety measures should be taken during construction work.
Cables can be laid in two ways - air and underground. When laying aerial, make sure that the wires do not touch trees, houses or other objects. Suspension height is calculated in advance. Laying in trenches is also carried out at a pre-calculated depth (from 80 cm) on a sand cushion.
Safety precautions
The construction site is a hazardous facility, therefore, to maintain the health and life of builders, safety precautions must be observed. It also applies to equipment that has special requirements. They are associated with negative environmental effects - the influence of ultraviolet radiation, weather conditions, high humidity. Materials must be non-combustible.
No corrosive chemicals should be present at the construction site.Only specialists with the appropriate qualifications and access group are allowed to work.
A grounding system and potential equalization elements must be created. For this, isolation transformers and a system for combining all open housings with the protective connectors in the outlet are used. In case of high humidity, protection is carried out using an RCD.
When creating a lighting group on a construction site, fixtures with a protection class of at least IP54 in a sealed enclosure are used. The documentation for the devices should say that they can be used outdoors.
It will take several light sources with the ability to move around the site. It is also necessary to put several fixtures in a temporary room where the work will be carried out, with mechanical stability.
