Voltage Stabilizers
Single- and three-phase automatic voltage stabilizers for installations at the end of a weak distribution network or feeding voltage-sensitive equipment.
- Rated power
- 1 – 1 600 kVA
- Phases
- 1 or 3
- Input range
- ±15 % to ±40 %
- Accuracy
- ±0.5 % to ±3 %
- Response
- 20 – 800 ms
- Protection
- IP20 – IP54
The problem these solve is unglamorous and common: a plant at the end of a long feeder where voltage sags at shift change and rises at night, damaging drives and lighting and shortening motor life.
Electrodynamic (servo) stabilizers correct slowly but hold accuracy across a wide input range. Thyristor stabilizers correct in milliseconds but with coarser steps. The right choice depends on whether the disturbance is drift or a step.
Ratings run from 1 kVA wall-mounted units up to 1 600 kVA floor-standing three-phase cabinets with independent per-phase regulation.
Key characteristics
Independent per-phase regulation
Three-phase units correct each phase separately, which is what an unbalanced rural feeder actually requires.
Wide input window
Output held to specification with input deviating up to ±40 % of nominal on servo constructions.
Full-load continuous rating
Rated for continuous duty at 100 % load and 40 °C ambient, not for an intermittent nameplate figure.
Bypass without interruption
Manual maintenance bypass allows service without dropping the load.
Construction
- Toroidal autotransformer with motorised carbon-roller contact
- Or thyristor tap-changing bridge for fast correction
- Forced ventilation with thermal cut-out
- Input and output circuit breakers and surge protection
- Manual make-before-break bypass
Available configurations
- Servo (electrodynamic) or thyristor correction
- Single-phase 1 – 30 kVA, three-phase 6 – 1 600 kVA
- Wall-mounted or floor-standing cabinet
- Independent or common phase regulation
- Remote monitoring via RS-485 / Modbus
Monitoring options
- Input and output voltage per phase
- Load current and percentage load
- Correction position and overtemperature alarm
- Modbus RTU register map for SCADA integration
2 series, 8 models
A series shares one design; the variants below differ by frame size and rating. This table is generated from the series definition — the variant list is never maintained by hand.
SVS — electrodynamic stabilizer series
Servo-controlled toroidal stabilizers with wide input range and high accuracy, for drifting supply voltage.
STS — thyristor stabilizer series
Static tap-changing stabilizers correcting in under 40 ms, for supplies with step disturbances rather than drift.
Principal applications
Suitable industries
Documentation for this family
PDFs supplement the pages above. Nothing here is required to establish whether a machine is a candidate.
- Download (mock)CatalogueVoltage Stabilizers — Product CataloguePDF · 4.2 MB · Rev. 05 · updated 2026-02 · EN, RO
- Download (mock)Data sheetSVS Stabilizer Series — Data SheetPDF · 0.6 MB · Rev. 03 · updated 2026-02 · EN, RO
- Download (mock)ManualOperation Manual — SVS StabilizersPDF · 2.2 MB · Rev. 03 · updated 2026-02 · EN, RO
- Download (mock)QuestionnaireTechnical Questionnaire — Voltage StabilizersPDF / online form · 0.2 MB · Rev. 01 · updated 2026-06 · EN, RO
- Download (mock)Data sheetSTS Thyristor Stabilizer — Data SheetPDF · 0.5 MB · Rev. 02 · updated 2025-12 · EN
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