Servo Stabilizer is an automatic voltage regulator, which primarily consists of the following features :

• Linear, plus / minus type vertical rolling contact voltage regulator
  For making these regulators, we use heavy section of electrolytic grade rectangular copper strip instead of copper wire in order to minimize the losses & increase the efficiency of equipment. We also employ self lubricating Carbon Roller Assemblies instead of ordinary Carbon Brushes that offers more reliability and trouble free performance of the equipment.
  
  
• Double wound buck / boost type series transformer
  In our Buck / Boost transformer, we make use of CRGO lamination to reduce iron losses. The coils of Buck / Boost transformer are wound with heavy section of multi strips electrolytic copper to minimize copper losses to get better efficiency of the equipment.
  
  
• Electronic control circuit and meter panel
  Automatic Voltage Controller usually consists of very simple electronic control voltage circuit for monitoring and controlling voltage, repair and maintenance of which is very easy. The regulator and Buck / Boost transformer are oil cooled, placed in same or separate sheet steel tanks. These devices are provided with radiators for effective cooling. The coils of voltage regulators & Buck / Boost Transformers are vacuum impregnated and oven dried as per IS.
  
  

Effect of Unbalanced Input Voltage between Phase to Phase
Industrial units located in residential and commercial areas, who do not have their own distribution transformer, have the problem of unbalance input voltage between phase to phase. They many also have the problem of frequent failure of three phase motors.

Normally unbalanced input voltage problem persist for few hours in a day and will have the following effects on the three phase motors

• With 5% Unbalanced Input Voltage between phase to phase, the LOAD will be unbalanced and the capacity of the motor reduces by 40%.
  
  
• Consumption of the three phase motor will increase by 20 to 25%.

Setting of motor relay is kept higher than actual required in order to avoid frequent tripping of the overload relays and to continue production. The motors which are particularly smaller motors upto 7.5 H.P. cannot withstand this high current for long duration. In many cases the motor burns out and this high current flows through the relays, contactors, cables etc. which result in failure of the same and in some of the cases may cause fire also.

The best solution for such units having unbalanced input voltage, is to install Servo Voltage Stabilizer with Individual phase Control.