Variable Auto- Transformer (Open & Box Type)The importance of continuously variable voltage in Electrical Engg. Works cannot be overemphasised, ARKAY 'VARISTAT' are made to make such continuously variable voltage most easily available.The intrinsic quality control check-ups under the supervision of highly experienced engineers ensures the ruggedness and reliability of operationSPECIAL FEATURESVARISTAT continuously variable Auto Transformers have many operating advantages and conveniences over other manually operated voltage control devices for alternating current useSmooth Control: The VARISTAT can be set to any output voltage within its range. Output voltage is continuously adjustable from zero to maximum.Small Size: The variable Auto Transformers is much smaller than any other type of control of equal rating.Better Efficiency: Very low losses under all loud conditions. Toroidal VARISTAT have low-loss grain oriented strip wound cores.Better Regulation: Output voltage is substantially independent of loud.Linear Output Volts: Output Voltage varies linearly with angle of rotation of control knob.Temperature rise: Less than 50 deg.C for continuous duty.Advanced Design: Excellent electrical specification is matched by rugged, compact construction. Brush replacement is simple and convenient.Two,Three or more units can be ganged on one shaft for series,parallel or three-phase operation.Long Life: When used correctly the VARISTAT has a very long operating life.The life of a VARISTAT is essentially the same as that of any standard fixed ratio power transformer. Indian Standards: All VARISTAT unit conform to I.S.S. 5142-1969Easily Read Dials: Dials are single - reading with large, clear numerals, easy to read at a distance.Wide range of models: VARISTAT are available in a wide range of models to suit various requirements. These includeOpen - for panel mounting purposeEnclosed - Suitable for table mountingPortable - with or without metersOil Cooled - for increased ratingsDouble Wound - Where the primary is isolated from the secondary prominant for manufacturer of servo-control voltage stabilizerHigh Frequency - for various loudsSpecial Voltage - 120v, 240v, 400v,etc.VARISTAT APPLICATIONSupply Voltage Correction, Boosting of low lines and line voltage stabilisation, either manually or automatically in automatic voltage stabilizersControl of D.C. voltage and current through rectifiers. Control of rectifiers in electroplating, battery chargers etc.Motor speed control in textile machines, blow moulding machines, injection moulding machines,printing and packaging machineries etc.Testing and calibration of voltmeters, ammeters, wattmeters, power-factor meters etc.Voltage and current control in development and experimental worksHeating control of ovens,furnaces, infra-red heaters etc. in production and experimental worksLighting control in theaters, auditorium, hotels, restaurant, photographic studios and dark-rooms, reading houses,etc.SPECIFICATIONSInput Voltage: The voltage that should be applied to the input terminals to make the dial calibration correct is 240v, 50Hz, 415v, 50HzOutput Voltage: The output voltage from the varistat is continuously adjustable from zero to 12.5% above the line voltage (i.e. 270V or 470V). The dial reads the approximate voltage.No load current: Less than 2% of full loadConstruction: Both single and three phase units are supplied enclosed in sheet metal covers, unless asked for open type construction for panel mounting,oil cooled units are supplied in sheet-metal tanks with or without cooling radiators.Current ratings: (single wound type)Click here for more details.