Ukraine has GOST 13109-97 "Norms of quality of electric energy in power systems for general purpose," which establishes performance standards and quality of electrical energy in electric networks of power supply systems for general purpose three-phase and single-phase alternating current frequency of 50 Hz at the points joined by electric network that are owned by different consumers of electricity, or electricity receivers (point universality).

However, standards GOST 13109-97 currently not controlled and often not respected producers of electricity through depreciation of equipment as well as economic reasons. Emerging failure of power supply systems and consumers also have different effects on the electric grid. All this can lead to the appearance:

• high-voltage pulses of varying lengths (tens of nanoseconds to tens of microseconds)

• voltage dips below acceptable,

• surge,

• fluctuations in voltage and frequency,

• high frequency noise.

To reduce the impact of these influences at work electricity consumers

applied voltage. Voltage can be installed to improve the quality of individual power consumers of electricity and power supply systems of apartments, houses, offices and even businesses. Also, most of the stabilizers protect consumers of electricity at a dull electricity. However, voltage stabilizers do not provide uninterrupted power, as most disabled at the complete disappearance of the input voltage.

When choosing a variable voltage stabilizer should know that the device automatically maintains on its output voltage in the normal range if the voltage at its entrance is in a certain range. When you exit the input voltage outside this range load stabilizer can be switched off if this feature is.