Construction begins with engineering!

Estonian Electrical Safety Act demands that the first step for all constructional and renovation works that require changing of existing electrical installations must be planning an electrical design. The persons who practice electrical design must be certified by Technical Inspection Centre. Persons and companies who provide their services in the field of special requirements as electrical designing and electrical installation works must be registered in Register of Economic Activities due to Register of Economic Activities Act.

Elektri Projekt OÜ conforms to the criteria set for inspection bodies of type B (up to 1000 V) however we are able to provide designs for higher voltage areas using help of subcontractors.

Why is it important to have an electrical design before starting the actual installation process?

Electrical designer has TIME and WILLING to determine the most suitable solution matching for your needs.

–       The cost of electrical design remains below 5% of electrical installation works and below 1% of the cost of overall construction. Having proper electrical design it gives you the opportunity for better overview of the costs of installation works and ability for minimizing those costs. A well drawn-up electrical design makes the comparison of different offers for installation works more transparent and comparable due to the predetermined scope and the quality of installation.
–       Electrical designer has no self-interest for putting in design so – called „cost effective“ solutions. Which may conform to the criteria of legislation de jure but are not corresponding to the best interest of the client needs de facto. It may consist of problems related to the exploitation expenses of the installation in the future, reduced ease of use and comfort, short lifetime and overall safety of the installation.

Collaboration as the key to success

The best outcome of electrical design as design in general depends on the successful collaboration between customer and electrical designer. As the buildings get more sophisticated the main focus of the design slides to the smooth collaboration between the designers of the different technological parts.

It is important to identify the needs and wishes of the customer first. As well to determine the possibilities that customer can allow. Electrical designer´s mission is to point clients` attention to the different aspects and options onto what ordinary people will hardly come planning their electrical systems. This complex initial data is for the electrical designer to form the electrical design following all the relevant latest standards and acts. It is a privilege of small engineering companies like Elektri Projekt OÜ to serve their clients with personal care.

As electrical installation is only one part of the technological networks of the building it is important to cooperate with the rest of the designers of the technological networks (water and sewage, heating and ventilation, architecture, interior decoration etc). This way is gained the best outcome for the construction and ensured further harmonious construction process with optimized expense for time and labour. The harmonious collaboration of the different designers helps to prevent unwanted surprises that might emerge during the actual construction process. There may arise „surprises“ like some ventilation devices do not have electrical feeding cables or heating system does not have proper automation cables etc. It makes times more expensive to resolve all this kind of errors during construction and can turn out that it is not possible to provide the original design.

How to get started?

It is smart to do some homework before addressing to electrical designer. The future owner of the building should be aware of the places where his dining table, couch, TV-set, refrigerator etc. is going to be to help electrical designer to plan socket outlets, luminaries in the right places. This is initial for turning the future residence in that building as much ergonomic and cosy as possible.
Here is a link to handy designer´s guide „Electrical needs at home“. It helps to estimate and draw up all necessary electrical appliances at home to present it as the initial material to electrical designer. This calculation helps to assess your electricity consumption needs and to choose the desired main circuit beaker amperage before filling the application for connecting to the power grid.

It is recommended to consult with the electrical designer for getting help with determining the desired main circuit beaker amperage because the average electricity consumers may not know their actual needs. It is significantly expensive to buy too large main circuit and on the contrary it may not be possible to enlarge the existing main circuit in the future due to power deficiency in the power grid.

The additional precondition for drawing an electrical design is existence of the architectural design in electronic format. It is the base where electrical designer can add all relevant data. It is possible to make concept design without architectural base but not to draw other building design stages: preliminary building design, basic building design and building design.

Essential for drawing an electrical design:

– terms of reference from customer
– technical terms issued by local power grid
– existence of architectural design in electronic format (.dwg, .drw …)

Different phases for accomplishing an electrical installation

1. Before starting a new electrical installation project or changing the terms and conditions of supply of electricity in the existing place of consumption you will need to submit connection application where is shown requested main circuit beaker rate. You can use our help in choosing needed main circuit beaker rate. You can read more about connecting to power grid here.
2. Electrical designer will draw a design
3. You can take competing bids for installation works form different contractors and choose most suitable for your needs.
4. Contractor will perform installation works leaded by person certified by Technical Inspection Centre.
5. Contractor will draw a construction design where potential variation of completed installation from building design is fixed.
6. Contractor will perform assessment of conformity of electrical installations and issue declaration of conformity of the electrical system.
7. You / contractor will hand out a copy of the certificate of conformity of the electrical system to the power grid.

What is high voltage, low voltage and automation system?

Standard EVS 811:2006 „Building design“ divides electrical installations into high voltage, low voltage and automation systems.

High voltage system is commonly known as external electricity networks and internal electricity supply systems plus lighting systems and some 230/400V security and fire safety systems.

Low voltage system is generic term for electrically operating technological systems which idea is not power transmission but assuring performance of some other technological system. This kind of systems are: TV, computer- and telephone communication networks, door phone and access control systems, video surveillance systems, fire alarm systems etc.

Automation system is complex quantum of devices generally used for controlling building climate control systems as AC, ventilation, heating. For instance this kind of systems are KNX / EIB building automation i.e. intelligent building systems.

Building design stages

During the design process the same terms of reference are given at different level of preciseness and range.

There are four different building design stages:

Concept design is helpful for planning necessary electrical appliances using location simulation for future rooms and furniture siting. It is good to use this data for estimating future electricity consumption level for submitting connection application to power grid.

Preliminary building design determines together with architectural design the technological level of the building. In this stage general review of the system and places of electrical distribution boards are given. Preliminary design is provided with relevant documentation (ownership right documentation, layout of building site, terms of reference from customer, connection agreement for connecting to power grid etc).

In basic building design all technical parameters are given in a rate of preciseness which is possible before choosing the exact installation methods and materials. In this stage layouts of the floors are given, centre schemes are drawn, rated currents for circuit breakers and cross sections for cables are calculated, routes for cable trays are determined, main characteristics of the appliances and luminaries are given etc.

Building design is a stage where basic building design is conclusively detailized. Here are given installation methods and brands of the materials which are used for installation. System parameters and problematic places of different potentially overlapping technical systems are specified.