* About belotti 


BELOTTI VARIATORI SRL has been active in the electromechanical industry since 1904.

In 1946, we began the production of toroidal ariable autotransformers in Milan under the licence of General Radio.
In 1971, we started the production of voltage stabilizers and in subsequent years increased the range till 3 MVA.
Nowadays, backed by more than fifty (50) years of experience in developing our range of products,
we have become a leading manufacturer of voltage regulation equipment.

BELOTTI VARIATORI SRL is a dynamic export oriented company who’s efforts at satisfying the client originate from a collective
package comprising a vast technical know-how, experience, the assurance of quality and strict adherence to various statutory regulations and/or standards for the safety of life and property.

We are located in Milano with plants occupying 3.000 m² comprising office, factory and    djacent units. We are suppliers for most  important groups all over Europe . Africa, Middle East and The Soviet Union. The experience acquired over these years has been essential for complying with the high-quality

standards met with in our export activity. The R&D department ensures a progressive technical advancement through continuous  xperimentations and innovations to produce high quality and reliable products capable of adapting to different environmental conditions.




Our BST range of Automatic Voltage Stabilizers manufactured in Milan (Italy), meet the requirements Of most applications where stable output is necessary.

The correct operation of all electrical and electronic equipment requires a constant voltage supply in order To function correctly

meanwhile, mains voltage values are often subjected to considerable fluctuations that drives the necessity to have machines able to deliver a constant output voltage, irrespective of any line input voltage variations.


* Features 


The BST is a Servo Controlled Stabilizer that has a number of features, which include the following :

• Extremely high efficiency (mostly 98% or better)

• Virtually zero waveform distortion (THDi/THDu)

• Very low internal impedance

• Negligible phase shift

• Unaffected by low system and/or load power factor

• Output voltage stability+/- 1%

• Negligible temperature drift

• Immune to frequency variation from 47 to 63 Hz

• Faster output voltage correction

• Elimination of motor switching spikes




The main components of the three-phase version of the equipment are

-        3 x single-phase ‘buck/boost’ transformers

-        3 x motorized single-phase autotransformers

-        3 x electronic control cards

With continuously variable transformer ratio ( voltage regulator )