Voltage stabilizers REG 1-2800kVA

REG-M/REG-T/REG-Y stabilisers are Aunilec’s technological and innovative answer to this problem, permitting to supply electric users with a voltage stabilised to the rated value they have been designed for even in presence of strong harmonic distortions.

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REG-M (single-phase) 1kVA-320kVA

REG-T (three-phase) 3kVA-780kVA

REG-Y (Independant phase regulation) 3kVA-2800kVA


  • Extremely high reliability
  • Wide range of variation network compensation
  • Stabilized voltage with high precision
  • Stabilization of high power use

The wider use of equipment with non linear absorption such as rectifiers, speed variators, drives, switching power supplies, has caused, besides traditional and well known voltage fluctuations, the spreading of a new insidious type of electrical fault: harmonic distortion. This fault “deceives” traditional stabilising systems that, in its presence, read wrong input voltage values. As a consequence a voltage is delivered with an efficient value that differs from the rated one, becoming greater as the harmonic distortion of the mains increases.REG-M/REG-T/REG-Y stabilisers are Aunilec’s technological and innovative answer to this problem, permitting to supply electric users with a voltage stabilised to the rated value they have been designed for even in presence of strong harmonic distortions.

Power supply interferences and failures

Failures on the distribution lines, atmospheric discharges, continual load variations and disturbances generated by the users make it impossible to guarantee always a steady voltage within the tolerance bandwidth stipulated in the supply contract with the electric energy producer. Very often the tolerance is insufficient for more sensitive facilities. Other times the mains voltage reaches levels that exceed the foreseen rated value by 15, 20 or even 25%. The voltage fluctuations are particularly treacherous interferences since they are not seen and can only be detected by using specific equipment. When such interferences are present, the electrical equipment seems to maintain correct operation but disguises serious problems that at times are beyond repair. Even an ordinary light bulb, if overpowered by 10%, continues to give light, but halves its operating life.

Voltage stabilisers Aunilec

Voltage variations

The situation becomes much more serious in the case of voltage variations on more complicated equipment.

  • a computer may become damaged or make unexpected errors.
  • a laser cutting machine undergoes changes in the “laserbeam mode”, resulting in cutting burrs or the shutting off of the beam.
  • a transmitter gives signal distortion and its components age more quickly.
  • an electric drive causes undesired changes in the speed of the powered motor and damage to the data storage and power terminals.
  • an “electromedical” device gives incorrect results, wastes expensive reagents and loses the samples to be analysed.


REG-M/REG-T/REG-Y are registered names of two series of electrodynamic voltage stabilisers that offer a reliable and tested economic solution to inconveniences caused by voltage fluctuation. To use REG stabilisers is a real investment because the elimination of the inconveniences means a reduction in costs and anincrease in productivity. Very often it is only necessary to avoid a few minutes machine downtime or just one failure to repay the cost of the stabilisers.

REG are particularly suitable for applications that require:

  • high reliability. For example they can be installed in areas with difficult access, subject to critical environment conditions due to cold, high temperatures, humidity, atmospheric discharges.
  • capability to compensate wide mains voltage variations (both symmetrical up to ±30%, and asymmetrical from -35% to +15%). This is a typical requirement of equipment installed in areas that are far from the distribution cabin and in fast developing countries.
  • high precision of the stabilised voltage. Ideal condition for calibration and inspection stands, electric furnaces, professional lighting systems.
  • stabilising of high power services or with a strong inrush current, such as: motors, air conditioners, compressors, pumps.
  • simple and limited maintenance. Most important where it is difficult to find qualified personnel for servicing.

Fonctionnement régulateur de tension Aunilec

Operating principles

REG-M/REG-T/REG-Y regulate through a series transformer. A static control circuit drives the variable autotransformer that supplies the required voltage to the series transformer either in phase or phase opposition to bring the mains to the rated value. The three-phase stabilisers are available in two versions:

  • T models which regulate on the average of the three phases and are therefore suitable for balanced lines or for a maximum load unbalance between the phases up to 50%.
  • Y models that, having three separate control circuits, individually regulate each phase and are therefore suitable for unbalanced lines and load unbalance between phases up to 100%.

REG - Voltage stabilizers models

  • REG-M: single-phase network 230V models.
  • REG-T: Models for 400V three-phase network (regulation on the 3 phases average).
  • REG-Y: Models for 400V three-phase network (independent phases by regulation).

General features

Aunilec voltage regulators are available in power rating from 1 kVA to 4750 kVA. Models up to 100 kVA can usually be delivered ex stock. Upon request we can supply stabilisers with the following characteristics:

  • single-phase voltages: 100-110-115-120-127-200-220-230-240-265-277 Volt
  • Three phase voltages: 208-220-230-240-380-400-415-440-460-480-500 Volt
  • Frequency: 50 or 60 Hz.
  • Indoor versions (IP20, IP21, IP31, IP54), outdoor versions (IP54), and open frame versions IP00.
  • Special versions fitted with: ammeter, frequency meter, multi-function meter, input or output circuit breaker (with or without earth leakage), manual or automatic by-pass, isolating transformer, surge arresters (lightning protection), over/under voltage protection, thermal relay, soft start, reversed phase sequence and phase failure protection, remote control, tropicalised versions.
Caractéristiques régulateur de tension Aunilec


REG-M/REG-T/REG-Y ensure the “true RMS value” of the voltage with an accuracy range that varies according to the model from ±0.5% to ±1.5%, even where strong harmonic distortions are present on the line.

Fast response

The advanced electronic control circuit ensures a fast response, from 11 to 50 ms/Volt according to the model. A controlled deceleration minimises overshoots.

Overload capacity

A typical characteristic of the REG regulation system. In fact, they can support without damage overloads up to 10 times the rated current for 10 milliseconds, 5 times for 6 seconds and 2 times for 1 minute.


At full load the range is from 96% for small models to 98% for the larger units.

Insensitivity to power factor and load variations

The REG series operating principle ensures that the equipment accuracy and regulation speed characteristics remain unaltered under any load conditions, with inductive or capacitive loads.

Insensitivity to frequency variations

The servomotor control circuit operates correctly with mains frequency variations up to ±5%.

Negligible waveform distortion

The high quality materials and their correct use ensure that harmonic distortion is always less than 0.2% underany working conditions.

Low intemal impedance

Installation of REG-M/REG-T/REG-Y in already existing systems does not require a new calculation of the protections since their internal impedance varying from 0.52 to 0.015 ohm does not significantly affect the line impedance.

Operating temperature

REG series are designed to work correctly at a maximum ambient temperature of 40°C in the most demanding conditions: continuous operation, full load and minimum input voltage. Models suitable for operation at temperatures higher than 40°C are manufactured on request.


The continual improvements that the REG-M/REG-T/REG-Y have undergone in over 50 years of activity during which our partner has manufactured over 430,000 stabilisers have obtained an exceptional MTBF for these devices.

Conformity to standards

REG-M/REG-T/REG-Y conform to the requirements of the following standards: Electro Magnetic Compatibility 2004/18/EC and following amendments; Low Voltage Electrical Equipment 2006/95/EC and following amendments.