Introduction :
Wherever electricity is used, SAMSTAT has helped make it more versatile, By providing an easy and efficient source feeding power at variable voltage. If you are not yet familiar with SAMSTAT Control System, you are missing some important benefits of using electric power. SAMSTAT is Continuously Variable Voltage Autotransformers. They usually form part of system in which other components such as transformers, rectifier stacks,etc. are used as power components, and error sensing devices and servodrive motors used for automatic operation. Our engineers are well experienced in such applications and are always available for consultation to prospective users.
SAMSTAT is an autotransformer, using a round strip wound core, instead of the usual E & I laminations. The entire winding is in a single layer, with a small gap left between start and end of the winding.
The proportion between iron section and copper turns is such that at the maximum applied AC voltage of 50 Hz, it does not get saturated and is designed to take only a small magnetizing current.The applied voltage is uniformly distributed over the winding. Thus, if 240 Volts are given to 240 turns, every turn shares one volt.
Voltage between, say 10 consecutive, Turns is thus, 10 Volts.By carefully baring the insulation of the wire over one face, a sliding brush is made to contact any turn of the winding. The output is taken between one end and the brush arm. The brush, while moving, contacts the next turn before it breaks away from the previous. Thus, there is no interruption in output voltage, while brush slides along thewinding’s contact surface.
The “Shorting” that the brush produces between the two turns, does produces between the two turns, does produce a current that circulates between them, but it is quite small to produce any undesirable effects like heating or sparking. This is because, the voltage between the two consecutive turns is very small. Being a true transformer, the maximum voltage available is made about 12% higher than the input voltage.
The Maximum Current that can be drawn depends on the size of the wire used. The important specification of SAMSTAT model is the maximum current it can give out to the load. Models from 0.7 Amp to 200 Amps are made.
HOW ABOUT SAMSTAT FOR 3 PHASE SUPPLY.
They are made by connecting three single phase SAMSTAT together. The brush arms are moved by a common shaft. The three windings are connected in Star and the Star point is connected to the neutral of the system. Thus, a 3 Phasevoltage variable from zero to 440 Volts is obtained.
SAMSTAT are available with motordrive. The type of motor used for driving is specially made for this application. It is 240 Volts AC motor operating with speed of 60 RPM. Synchronous at 50 Hz. It is instantly reversible and can be stopped without overrun. Gears between motor and SAMSTAT shaft are used toget lower speed. The time taken for the full sweep is the specification used, e.g.. 15 seconds, 30 seconds etc. That is thetime taken for the brush to move from zero voltage position to the maximum voltage position.
3 Ph. OIL – COOLED SAMSTAT
40 AMPS 3 PHASE OIL COOLED SAMSTAT
50 AMPS 3 PHASE OIL – COOLED SAMSTAT
60 AMPS 3 PHASE OIL – COOLED SAMSTAT
75 AMPS 3 PHASE OIL – COOLED SAMSTAT
100 AMPS 3 PHASE OIL – COOLED SAMSTAT
150/200 AMPS 3 PHASE OIL – COOLED SAMSTAT
40 AMPS 3PHASE OILCOOLED SAMSTAT
40 AMPS MODEL has no external cooling tubes.
The above drawing shows it with front side of tank cut away to show the internal construction. Hand wheel drive.
Type 
40D – 3T 
MAX.OUTER DIMENSIONS L x W x H cms 
69 X 62 X 108 
NETT Wt. WITH OIL – Kg 
245 
SHIPPING Wt. (WITHOUT OIL)  Kg 
320 
OIL QUANTITY  Liters 
115 
50 AMPS 3PHASE OILCOOLED SAMSTAT
50 AMPS MODEL shown above has cooling tubes on two sides only. The above drawing shows side view, for a model with Motor – drive. The box on right top side is for terminal.
Type 
50D – 3T 
MAX.OUTER DIMENSIONS L x W x H cms 
69 X 84 X 108 
NETT Wt. WITH OIL – Kg 
280 
SHIPPING Wt. (WITHOUT OIL)  Kg 
365 
OIL QUANTITY  Liters 
125 
60 AMPS 3PHASE OILCOOLED SAMSTAT
60 AMPS MODEL has cooling tubes on all four sides. The above drawing shows front view, for a hand drive model.
Type 
60D – 3T 
MAX.OUTER DIMENSIONS L x W x H cms 
91 X 84 X 108 
NETT Wt. WITH OIL – Kg 
310 
SHIPPING Wt. (WITHOUT OIL)  Kg 
445 
OIL QUANTITY  Liters 
130 
75 AMPS 3PHASE OILCOOLED SAMSTAT
60 AMPS MODEL has cooling tubes on all four sides. The above drawing shows front view, for a hand drive model.
Type 
75D – 3T 
MAX.OUTER DIMENSIONS L x W x H cms 
103 X 91 X 140 
NETT Wt. WITH OIL – Kg 
540 
SHIPPING Wt. (WITHOUT OIL)  Kg 
645 
OIL QUANTITY  Liters 
260 
100 AMPS 3PHASE OILCOOLED SAMSTAT
100 AMPS MODEL has two rows of cooling tubes on all sides. Terminal are housed in the box at the top as shown at the right in the above drawing for hand driven model.
Type 
100D – 3T 
MAX.OUTER DIMENSIONS L x W x H cms 
91 X 84 X 108 
NETT Wt. WITH OIL – Kg 
310 
SHIPPING Wt. (WITHOUT OIL)  Kg 
445 
OIL QUANTITY  Liters 
130 
150/200 AMPS 3PHASE OILCOOLED SAMSTAT
150/200 AMPS MODEL has two cores connected in parallel per phase , through balancing reactors. It has two rows of cooling tubes on all the sides. The above drawing shows a motor driven model with the front side of the tank cut away to show the internal construction.
Type 
150/200D – 3T 
MAX.OUTER DIMENSIONS L x W x H cms 
91 X 84 X 108 
NETT Wt. WITH OIL – Kg 
310 
SHIPPING Wt. (WITHOUT OIL)  Kg 
445 
OIL QUANTITY  Liters 
130 
