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 30%.
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.
Ministab and Sterostab are registered names of two series of electrodynamic voltage stabilizers that offer a reliable and tested economic solution to inconveniences caused by voltage fluctuation. Ministab and Sterostab employment is a real investment because the inconveniences elimination means a reduction as costs and an increase as productivity.
Both available in single-phase and three-phase solution, they satisfy different power ranges.
Ministab: 1 – 120 kVA;
Sterostab: 16 – 4000 kVA.

Tecnical document request for these products

MINISTAB

They supply true RMS stabilized voltage even in presence of high harmonic distortions in the power distribution network.

Voltage stabilizer Ministab Irem

Voltage stabilizer Ministab Irem

MINISTAB are available for ratings from 1 to 120 kVA, single-phase and three-phase versions:
– M models: single-phase stabilizers;
– T models: three-phase stabilizers with adjustment on the average of three phases;
– Y models: three-phase stabilizers with independent adjustment on each phase.
Standard nominal voltages:
– Single-phase 230 V;
– Three-phase 400 V.
Special voltages:
– Single-phase 100, 110, 115, 120, 127, 200, 220, 230, 240, 265, and 277 V;
– Three-phase 208, 220, 230, 240, 380, 400, 415, 440, 460, 480 and 500 V.
Input  voltage variation: symmetrical ± 10% to ± 30%,  asymmetrical up to + 15% – 35%.
Frequency: 50 or 60 Hz.
Accuracy: ± 0.5% to ± 1.5%.
Open version: IP00.
Indoor versions: IP20, IP21, IP31 and IP54.
Outdoor versions: IP54.

STEROSTAB

Voltage Stabilizer Sterostab Irem

Voltage Stabilizer Sterostab Irem

They supply true RMS stabilized voltage even in presence of high harmonic distortions in the power distribution network.
STEROSTAB are available for ratings from 16 to 4000 kVA, single-phase and three-phase versions:
– M models: single-phase stabilizers;
– T models: three-phase stabilizers with adjustment on the average of three phases;
– Y models: three-phase stabilizers with independent adjustment on each phases.
Standard nominal voltages:
– Single-phase 230 V;
– Three-phase 400 V.
Special voltages:
– Single-phase 100, 110, 115, 120, 127, 200, 220, 230, 240, 265, and 277 V;
– Three-phase 208, 220, 230, 240, 380, 400, 415, 440, 460, 480 and 500 V.
Input voltage variations: symmetrical ± 10% to ± 30%, asymmetrical up to + 15% and – 35%.
Frequency: 50 Hz or 60 Hz.
Accuracy: ± 0.5% to ± 1.5%.
Open version: IP00.
Indoor versions: IP20, IP21, IP31 and IP54.
Outdoor versions: IP54.

Technologies and functioning

Ministab and Sterostab 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%.
schema stabilizzatore di tensione modello T
  • 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%.
schema stabilizzatore di tensione modello Y3

 

Ministab and Sterostab work properly with networks both 50 and 60 Hz.

Ministab e Sterostab can have different degrees of protection:

  • IP21: protection degree suitable for equipment installed indoor and in rooms free of dust and splashing;
ministab e sterostab per locali chiusi
  • IP54 INDOOR: guarantees the protection of the stabilizer against dust and splashing, therefore it is suitable for equipment installed in dusty and also very hot, but not suitable for outdoor installation;

IP54 per locali polverosi interni

  • IP54 OUTDOOR: suitable for outdoor installation because ensures the protection of the stabilizer against dusts, sprays and solar radiation.
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