Description :

Servo – Controlled Automatic AC Voltage Stabilizers of ‘AE’ make are of ‘Electro – Mechanical (EMS) type. The purpose of voltage stabilizer is to receive a fluctuating AC voltage of large amplitude & deliver an almost constant voltage, which remains within a very narrow band (± 1%) of the nominal voltage – quality of the AC voltage remains unchanged. The voltage variations, which have become a common phenomenon in current power supply system, cause havoc in modern complicated & sophisticated equipments. The voltage stabilizers are meant to take care of this problem & protect the equipments. They ensure longer life of the equipments & also drastically cut down electricity consumption of equipments leading to continuous reduction in electricity bills. Thus, they play an important role in energy conservation which is need of the day.

The EMS type AC voltage stabilizer basically comprises of the following –

  • Dimmerstat (Continuously variable voltage auto transformer).
  • Buck – Boost Transformer (Optional upto 5kVA 1Ph / 15kVA 3Ph).
  • AC Step-synchronous motor.
  • Solid state electronic control circuit.
  • Two switching triacs.
  • MOVs for surge suppression.

Features :

  • Waveform distortion – nil.
  • 98 – 99% efficiency (achieved by optimum design & by use of imported hi-quality CRGO laminations & copper of 99.9% purity).
  • Speed of correction up to 70V/sec.
  • Response time – less than 20 m/sec.
  • Immune to load PF & supply frequency variations.
  • Power loss 2% max.
  • Duty cycle continuous.
  • Life expectancy – 20 – 25 years.
  • Easy & simple maintenance (with plug-in PCBs).
  • Protections – over voltage / under voltage / overload / single phasing    (optional).
  • Very high reliability.
  • Considerable short time overload capacity.
  • Output voltage setting (by potentiometer in Auto Mode & by ‘Raise’ / ‘Lower’ Push Button in Manual Mode).
  • Operation – Auto or Manual.
  • LED Indications for Input Voltage ‘High’ / ‘Low’.
  • Metering (Analogue or Digital) – AC voltmeter with / without selector switch.
  • Non-standard requirements can be catered to, such as AC Ammeter, Frequency Meter, PhaseSequence Meter, Single Phasing Preventer, Stabilizer by-pass arrangement, etc.

The Control & Monitor System of these Voltage Stabilizer have following standars features

  • Alarm lamps which light up when the input voltage goes above or below the maximum or minimum specified Input Voltage
  • Voltmeter, with selector switch, to indicate either input or output voltage.
  • Screw driver adjustment to set the output voltage to the exact specified level.
  • ‘Auto-Manual’ selector switches to select the mode of working of the Stabilizer. In the event of failure of Automatic control, the unit can be used under Manual control.
  • Push Button Switches marked “Raise” & “Lower” to increase or decrease the output voltage when unit is under manual control.
  • Easily replaceable and serviceable printed circuit cards.(PCB)

Following deviations from standard types of Stabilizers are possible, subject to confirmation

  • Non-standard input voltage range, output voltage and KVA rating.
  • Automatic Alarm/Power cut-off in case of over voltage, under voltage, overload and phase failure.

Electrical specifications :

Model : EMS - 12
Type : Indoor, Floor Mounting.
Cooling : Air - Cooled / Oil Cooled / Air - Oil Cooled.
Input : 160 - 260V / 180 - 250V, 1 Phase AC.
300 - 460V / 360 - 460V, 3Phase, 4 Wire (or 3 Wire if required)
AC (Balanced or Unbalanced).
Output : 230V / 240V ± 1%,1 Phase AC.
380V / 400V / 415V ± 1%, 3Phase AC.
Frequency : 1 kVA - 2000kVA
Capacity : 50 - 60Hz.
Insulation Resistance : Not less than 5 Mohms at 500V DC
Dielectric Test : 1.5kV RMS for 1 minute.
Operating Temp : 0°C to 50°C
Storage Temp : - 9°C to 70°C
Humidity : upto 95% RH
Conforms To : I.S.9815

Notes :

  • Input & output voltages, other than specified above, are available on specific request.
  • For 3 Phase balanced supply system, a common controller, connected to any one phase is employed.
  • For 3 Phase unbalanced supply system, 3 individual & independent controllers, one for each of the 3 Phases, are employed.
  • Oil should be ‘Transformer Oil’ Conforming to IS 335, I.E.C. 296.

Mechanical Construction :

ac voltage stabilizer-mechanical const

Applications :

CNC Machines, Air Compressors, Textile Machines, Lightings, X-ray & Medical Equipments, Engineering Units, Computers, Pump Sets, Transmitters & many other similar applications.

Ordering Information :

  • Model
  • Type
  • Cooling
  • Input Voltage (Balanced or Unbalanced)
  • Output Voltage
  • Capacity (kVA)
  • Protections (if required)
  • Non-standard metering.
  • With / without first filling of oil (only for oil cooled units).