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4.4 PANEL INDICATION & CONTROLS
Input on
:
This indicator shows the input availability
Output on
:
This indicator shows the output availability
High/low voltage indicator
:
This indicator shows the input high or input low i.e.
beyond or below the range of voltage stabilizer.
Auto/manual switch
:
This switch facilitates automatic and manual mode of
operation to the stabilizer. In auto mode the output
voltage of the servo is always in conjunction with
increase/decrease switch is used to set output voltage
to the desired level.
Increase/Decrease switch
:
This switch work only in manual mode to Increase /
decrease the output voltage.
Output/cutoff
:
If output of servo goes above 260 in each phase ± 2V
Ac or falls below 190/200V cut-off. The indicator
shows cut-off condition of the corresponding phase.
Voltage Adjust
:
This is potentiometer with which output of the Servo
can be set to the required level between 220V and
240V in each phase in Auto mode.
Reset-auto/ Manual
:
When the reset switch is in Auto position, the Output
will available automatically. When the Reset switch is
in manual position, the output Will available by using
of 3ph output
ON/OFF
:
Push button switches
4.5 OPERATING PRINCIPLE
The electronic control manages the output voltage of the stabilizer permanently, providing a correction
signal the Servo motor, in order to achieve the wanted output voltage with an accuracy of ±1 %
(adjustable from ±0,5 % up to ± 5 %). The motor acts over the toroidal autotransformer (Variac), by
increasing or decreasing the voltage, by moving the brush in the variable tap in one way or to the other.
Servo Voltage Stabilizer utilizes an autotransformer (variac) coupled with motor and BUCK BOOST
transformer. The BUCK BOOST transformer has two winding i.e. primary and secondary. Primary connected
to AUTOTRANSFORMER (Variac) and secondary to series with supply line. The primary voltage of BUCK
BOOST transformer controlled by auto transformer moving arm position with the help of motor. Thus adding
