Servo Voltage Stabilizer

Servo Voltage Stabilizer is commonly observed that, AC main supply is never 230 Volt or 415 Volt, but varies from 150 Volt – 300 volt and 300 Volt – 500 Volt. The difficulties caused by them are well known, such as Over Load Condition, Line Losses, Poor Power Factor and several other reasons. Generally constant voltage which is required to load is never constant, but in fluctuation manner. It is observed that during the daytime, the voltage is quiet low and during the night the Voltage is high then the normal.

This fluctuation in supply system results frequent breakdown, low production and also loss of energy. The performance of any electrical equipment is optimum at its rated voltage. Both over / under voltages are harmful for the system. The under voltage reduces efficiency whereas the over voltage shortens the life.

The power agencies insist the consumer to fix the capacitor to improve power factor to get better results in power saving. But Voltage is far more important factor to save the power loss

In case of very Low / High voltages, the telecom systems are powered by DG sets. Our Line Conditioner Unit meets the requirement of input voltage variation from 110V – 280V (Single phase) and 300V – 500V (Three phase). 240V – 500V is also available on demand.

In India, there are large voltage variations in the mains power supply. To overcome this problem, we are offering Line Conditioner Unit.


Servo Stabilizers are automatic line Voltage corrector using synchronous motor in close loop control. The stabilizer employ continuously variable auto transformer, buck-boost transformer, AC synchronous motor, state of the art IC closed loop control system with all protection, metering, indication and control system to give desired output voltage within the specified limits for a range of input voltages. Provision for manual correction of voltage can also be provided.


Parameter Single PhaseUnit Three Phase Unit
Rating 2 KVA to 50 KVA 6 KVA to 2000 KVA
2 Input Voltage Range a) 180V – 280V
b) 160V – 280V
c) 140V – 280V
a) 350V – 470V
b) 340V – 470V
c) 320V – 470V
d) 300V – 480V
e) 270V – 480V
f) 240V – 480V
Nominal Output Voltage 230V 400V
Output Voltage Accuracy ± 1% ± 1%
LineFrequency Variation 47Hz-53Hz . 47Hz-53Hz
Effect of Power Factor None None
Wave Form Distortion None added None added
Control Digital/Analogue Digital/ Analogue
Response Time 10 ms. 10m s.
Voltage Correction Rate
1. Air Cooled
2 Oil Cooled
25V / Sec.
15V/ Sec
40V / Sec
25V / Sec.
LCD Display (20 x 2 matrix) Date & Time, Input Voltage, Output Voltage & Current
Log book Memory (Non-volatile)
  • No. of Hrs. of operation on mains
  • Peak Current demand
  • Nos. of Abnormal High Voltage cut-off events.
  • Nos. of Abnormal Low Voltage cut-off events.
  • No. of Hrs. of operation on DG.
Programmable Features(Through 2-parallel way resettable passwords) HV cut-off set
.LV cut-off set.
O/L trip set
.Time delay set
Operating mode (auto/manual)
1. Air Cooled
2. Oil Cooled
2 KVA to 40 KVA & above
5 KVA to 1000 KVA & above
Efficiency 97%
Protection a) Automatic Switch-Off against:
· Under / Over-Voltage
· Over-Load & Short – Circuit
· Single Phasing
Surge Protection Class C Type Secondary surge Protection