Single Phase Variable Auto Transformer takes the input from 240 V - 50 Hz AC line and the output can be varied from 0 - 270 V. Single phase Variable Auto Transformer are available in projection Mounting and Flush Mounting types. Output of these Variable Auto Transformer at can be varied from 0 to 270 V input being 240 V - 50 Hz AC. Ganged Assemblies of 3 coils, connected in star are available for 3 phase supply. Contact arm of these coils are connected to common shaft. 3 phase Variable Auto Transformer takes the input from 415 V - 50 Hz AC and the output can be varied from 0 to 470 V. The input of these Variable Auto Transformers are 415 V - 50 Hz 3 phase AC and the output can be varied form 0 to 470 V. Variable Auto Transformer fitted with voltmeter, ammeter, fuse, switch, pilot lamp etc. can be made in portable type models with extra cost. For the control of the contact arm from a remote point, or automatic control of the output Voltage, Variable Auto Transformer can be made with motor drive. The motor is coupled to the central shaft of the Variable Auto Transformer and as motor rotates, the contact arm moves over the plated contact surface.

Variable Auto Transformers-1		Variable Auto Transformers-2

The motors are noiseless in operation and work on 240 - 50 Hz single phase AC. The rotation of the motor can be reversed by interchanging the motor connection by means of a SPDT switch. The sweep of the motor driven Variable Auto Transformer is about 330 (Degree sign) in 30 seconds/15 seconds/8 seconds.

Anodizing and Electroplating industries.
Measuring and Testing equipments.
Research Laboratories and Colleges etc.
Lighting control in Theatres, Studios etc.
Control of light heat, speed etc.

Excellent voltage regulation and efficiency.
No wave form distortion.
Simple and easy to handle.
Rugged mechanical construction.
Moderate temperature rise.
Smooth control of output voltage.
High short time surge current capacity.
Linear output voltage.