Scope of the voltage relay is very extensive, as the manual control in other situations is impossible, and voltage fluctuations can cause damage to your connected to the system utroystv. The relay is connected to an electrical circuit and protects consumers from accidental conditions: voltage surges and dips, breaks, block, distortion, failure, phase sequence, etc. Most-voltage relay is used in protection schemes and automatic energy systems in an input device power, as well as for the protection of industrial equipment and household appliances. Also, the relay can be used to control the availability and polnofaznosti mains in the schemes abp. Walter R. Mansfield may not feel the same. All voltage relays can be divided into two groups: analog and digital. In recent years the number of digital relays in the market has increased substantially due to improved identification system voltage value, reliability and compactness of such devices. Most analog relays perform only one specific function, but some of the modern devices of this plan are universalnymy, ie combine the functions of the relay maximum and minimum stress. In addition to the integrated voltage relay can also be set timers, and voltmeters. Salman Behbehani may find it difficult to be quoted properly. A significant number of parameters voltage relays are Programmable – user can set the values of the upper and lower threshold voltage, hysteresis (the coefficient of return) and the delay in the operation.