Servo Control Voltage Stabilizer Three Phase



SURVAS servo voltage regulators are an effective solution to the problem of voltage fluctuations. They are designed to give a stabilized output within +/- 1% of the nominal value. These servo voltage regulators are available in two configurations, namely Balanced load and unbalanced load regulators. The balance load type has a sensing circuit which detects the voltage variation in one phase and moves the motor such that three phase output is in the specified limit. The unbalance load stabilizers have separate motorized auto- transformers for each phase which are independently controlled to ensure desired output. The output waveform is completely distortion free and the regulation is unaffected by power factor. Various models are available corresponding to different input/output and KVA ratings.

Additional Features:

Automatic High/Low voltage cut-off. Overload & Short-circuit  protection.

Audio alarm at extreme input voltages.

Line-noise and surge suppression network.

Separate line current meter with rotary switch.

Single-phasing preventer for Balanced load application

Ultra isolation transformer at output (star-delta optional)


CNC Machines

Plastic Moulding Machines

Spark Erosion and Wire-Cut Machines. Mainframe computers.

Communication equipments like Radio and TV transmitters, Space applications. Operation Theaters, large X-ray machines, CAT Scanners.

Air conditioning plants.

Production plants, general heating and lighting equipments. Large testing laboratories.

Elevators and Escalators.

Centralized stabilization of domestic power.

Textile machinery like Autoconers, draw Frames and Power looms.

Diamond cutting / polishing machines.

Additional information


300v to 470v or 340v to 380v line – to – line, 3 phase 4 wire systems.
(Balanced or Unbalanced to be specified) _ or specified by customer.


415 volts +/- 1% line-to-line Nominal

Response Time

10 msec


96% or more.


Air cooled up to 100 KVA, Oil cooled for higher KVA ratings

KVA ratings

3 KVA to 1500KVA.