Constant Voltage Transformer


Constant Voltage Transformer

Optimum performance of sophisticated electronic equipment is highly dependent on the stability of the mains voltage. The continuously fluctuating mains supply, transients, spikes & surges produce harmful effects.

The CVTs are preferred over voltage Stabilizer as the Stabilizer have relays that are when switched cause the output voltage to be interrupted for a short time. This type of interruption or transient many not be good for computers. In comparison to voltage Stabilizer, the CVTs ensure a clean, spike-free and controlled output voltage.

'bluebird' constant voltage transformer gives an effective solutions to all these problems.

Constant voltage Transformer are based on Ferro-Resonance Principle & it consists of two basic components i.e. Ferro-Resonant transformer and capacitor.

'bluebird' constant voltage Transformer are ideally suitable for computers & like systems Data processing equipment, Bio - Medical equipment, Telecommunication equipment, Telex, EPABX, Electronic Typewriter, Fax Machines and any other sophisticated electronic equipment which requires a precise mains supply.


  • High reliability as no semi conductors/moving parts used.
  • Provide relatively sine wave output irrespective of quality of input wave shape.
  • Instantaneous voltage regulation.
  • Output highly isolated from mains for suppression of transients & spikes.
  • Short-term over LOAD capacity.
  • Intrinsic current limiting & short circuit protection.
  • Higher input voltage control range for LOADS less than rated load.


  • Place the CVT away from equipment and all magnetic display and storage devices like diskettes, monitors, tapes etc.
  • It is safer to connect CVT to mains supply through a 3 Pin socket ensuring thereby the availibility of proper 'Earth' connection.
  • Switch ON the CVT first then the attached peripherals and while switching OFF, switch OFF attached peripheerals first and then the CVT.
  • In case of supply from a generator, check frequency, CVT is not be used if frequency variation is beyond 50 +/-1Hz.
  • Switch OFF the CVT when not in use.
  • Not to be used for high inductive LOADS like motors.


  • Input Voltage : 180-260, at rated load
  • Output Voltage : 220/230V+/-1%
  • Frequency : 50Hz+/-1%
  • Response Time : 30 milliseconds
  • Efficiency : 90% (app) under full load condition
  • Output wave form : Sinusoidal
  • Wave form distortion : less than 4% under full load condition.
  • Load Power Factor : 0.75% lag to 0.9% lead
  • Ambient Temp. : -5o to 50o c
  • Effect of line frequency : 1.5% (app) change in output voltage for every 1% change in line frequency

Constant Voltage Transformer

CVT 3 KVA to 5 KVA