DIMMER / VARIAC (CONTINUOUSLY VARIABLE VOLTAGE AUTO TRANSFORMER)

 
     
 

DESCRIPTION

VARIVOLT' make continuously variable voltage auto-transformer. It is the most effective device for stepless, breakless & continuous control of AC voltage & therefore for various parameters, dependent on AC voltage.

The basic Varivolt is meant for operation from a nominal input voltage of 240V 1ph AC & can give output voltage anywhere between 0 to 240V or 0 to 270V AC by simple transformer action. Three such Varivolts connected electrically in star and mechanically in tandem, become suitable for operation from a nominal input voltage of 415V 3Ph AC and can give output anywhere between 0 to 415V or 0 to 470V.

   

ELECTRICAL SPECIFICATIONS

TYPE :

  • Flush Open Manual (Air Cooled) — F
  • Portable Enclosed Manual (Air Cooled) — P
  • In Tank Manual (Oil Cooled) — T
    'F', 'P', T suffixed by 'M' means motor operated models.

 
   

OPERATING VOLTAGE :

  • For Single Phase - 240V AC, 50-60 Hz. 1- ph.
  • For Three Phase - 415V AC, 50 -60 Hz., 3 - ph - 4wire.

CURRENT RATINGS :

  • For Oil Cooled models, 40,50,60,75,100,125,150, 200,300,400, 00,600,800,1000,1200,1500 A.
  • For Air Cooled models, the ratings are as shown below.
 
     
 

Maximum Current

0.7

2

4

8

10

15

20

28

Continuous Current

0.6

1.8

3.8

6.5

9

11.5

16

22

 
     
 

OPERATING TEMP : 0° - 45°C.

INSULATION RESISTANCE : Not less than 5 Mohms at 500V DC.

DIELECTRIC TEST : 2.5kV RMS for 1 minute.

STORAGE TEMP: -9°C to 70°C

HUMIDITY : Upto 95% RH

CONFORMS TO : I.S. 5142.

 
     
 

Motorised Varivolt uses 240V AC Step-Syn Motor having 60 rpm speed at 50Hz. With proper gearing higher torque at lower speed can be achieved. Standard gear ratios used provide sweep time of 8, 15, 30, 45, 60,120secs.

 
     
 

Features

  
 
  • Simple, rugged construction & High efficiency.
  • Coils made from high grade CRGO Silicon Steel & 99.9% pure copper.
  • High quality carbon brush used for current collection.
  • Negligible waveform & power factor distortion
  • Excellent short time overload capacity.
  • Remote operation possible by motorization.
  • Output voltage variation is smooth, continuous, beakless & linearly proportional to angular rotation.
 
     
 

Applications

  
 
  • Auditorium, Hotels, Conference Halls, Exhibitions, Laboratories etc.,
  • AC Voltage Stabilizers, Rectifiers, Battery Chargers.
  • Temperature control of Ovens, Furnaces.
  • Testing of Instruments, Relays, Circuit Breakers etc.
  • Welding, Electro-plating, Anodizing etc.
  • Colleges & Universities