Something basic - kWh
The kilowatt hour (symbol kWh, kW?h, or kW h) is a derived unit of energy equal to 3.6 megajoules. If the energy is being transmitted or used at a constant rate (power) over a period of time, the total energy in kilowatt-hours is the product of the power in kilowatts and the time in hours. The kilowatt-hour is commonly used as a billing unit for energy delivered to consumers by electric utilities.
The symbol "kWh" is commonly used in commercial, educational, scientific and media publications, and is the usual practice in electrical power engineering.
Other abbreviations and symbols may be encountered:
"kW h" is less commonly used. It is consistent with SI standards (but note that the kilowatt-hour is a non-SI unit). The international standard for SI states that in forming a compound unit symbol, "Multiplication must be indicated by a space or a half-high (centered) dot (?), since otherwise some prefixes could be misinterpreted as a unit symbol" (i.e., kW h or kW?h). This is supported by a voluntary standard6 issued jointly by an international (IEEE) and national (ASTM) organization. However, at least one major usage guide and the IEEE/ASTM standard allow "kWh" (but do not mention other multiples of the watt hour). One guide published by NIST specifically recommends avoiding "kWh" "to avoid possible confusion".
The US official fuel-economy window sticker for electric vehicles uses the abbreviation "kW-hrs".
Variations in capitalization are sometimes seen: KWh, KWH, kwh etc.
"kW?h" is, like "kW h", preferred with SI standards, but it is very rarely used in practice.
The notation "kW/h", as a symbol for kilowatt-hour, is not correct.
Protection of privacy thanks to the work electrician
Increasingly, the jobs performed within the framework of electrical services must mount installation, which is responsible for supervising the specified object. It turns out that electricians not only assume the camera, but very often they take to install intercoms or video intercoms, which largely can increase the safety of people living in the building. This is very important in facilities where daily scrolls many people, such as in high-blocks and so on. These modern systems make people feel much safer in their own home.
Electrical services around the clock
Very often it becomes necessary to call in an electrician in late at night. Many electricians who start their own business providing electrical services decides on all day business profile. This is of course, much more strenuous work system, but still so that you can greatly increase the number of customers using the services of a particular company. Such flexibility electrician to ensure that customers who are in the house there was a failure can ask for help at any time. This is important especially in larger cities, because living people there lead a very busy lifestyle and therefore the repair will be carried out for example in the evening.