• An automatic voltage regulator, AVR for short, is a device that is designed to automatically control, adjust or maintain a constant voltage level. Automatic voltage regulators come in a variety of sizes and designs. Only a certified electrician should handle this device as it involves a live electrical current.
  
  

Narrowing Voltage Ranges

• An AVR obtains a series of voltage levels that are then converted to a much narrower voltage range. For example, an AVR for a device with an input voltage range of +10 percent to -25 percent of the nominal input voltage will convert the range to a regulated voltage of +3 percent to -3 percent of the nominal output voltage.
  
  

Voltage Step Up or Down

• A voltage regulator with step up or step down capability converts nominal incoming voltage to a new voltage level of output. For example, it may a step up a 200V input to a 400V output. Conversely, voltage regulator step downs reduce the output voltage.
  
  

Single or Triple Phase AC Applications

• An AVR regulates the voltage level for single phase or triple phase alternating current devices. A single phase AVR regulates the voltage of triple phase applications by supplying three single phase loads. A triple phase AVR regulates all three phases concurrently or independently.