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Variable Transformers
7 Series · 58 Models
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Variable Transformers Overview
Variable auto-transformers deliver continuous, stepless AC voltage adjustment through a carbon brush moving over a toroidal winding. QDTB units adjust 0-250 V single-phase (TDGC2) and 0-430 V three-phase (TSGC2) from 0.5 kVA to 30 kVA, with smooth, precise output. Typical uses include laboratory testing, electric furnace temperature control, stage lighting dimming, and instrument calibration. DTY series covers special applications and TSZ2 premium requirements.
Available Series
TDGC2 Series
The TDGC2 series single-phase contact voltage regulators provide continuously adjustable output voltage from 0 to 250V. Used extensively in laboratories, testing, and industrial applications.
TSGC2 Series
The TSGC2 series three-phase contact voltage regulators provide continuously adjustable output voltage from 0 to 430V for three-phase power applications.
TSJA-TDJA Series
The TSJA (three-phase) and TDJA (single-phase) series oil-immersed variable transformers provide high-capacity continuously adjustable voltage output for heavy-duty industrial applications.
DTY Series
The DTY series intelligent contact voltage regulators feature digital display and microprocessor control for precise voltage adjustment with enhanced safety features.
TSZ2 Series
The TSZ2 series three-phase magnetic contact voltage regulators use electromagnetic principle for smooth voltage regulation with high reliability and long service life.
SCR Power Regulators Series
SCR (thyristor) power regulators provide stepless power control for resistive heating loads by phase-angle or zero-cross firing of thyristors. Rated 10–2000 A for single-phase and three-phase loads, they regulate power to electric heaters, furnaces and drying ovens with fast response and high efficiency.
Moving Coil Regulators Series
Moving coil regulators adjust output voltage and current by mechanically moving a coil within the magnetic circuit, changing the coupling and hence the reactance. Used in high-power test and laboratory applications requiring continuous, robust regulation with minimal contact wear.
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Application Scenarios
Laboratory Testing
Provides adjustable AC voltage for testing devices across their rated input range.
Electric Furnace Control
Stepless temperature control for resistance furnaces and heating elements.
Stage Lighting
Smooth dimming of incandescent stage and studio lighting.
Instrument Calibration
Precise variable supply for calibrating meters, sensors and relays.
Motor Speed Control
Voltage adjustment for small single-phase and three-phase motor speed regulation.
Education & Training
Safe, adjustable AC source for teaching labs and demonstrations.
Technical Advantages
Stepless Adjustment
Continuous 0-250V (single-phase) or 0-430V (three-phase) output with no steps.
Smooth Carbon-Brush Contact
Carbon brush on a toroidal winding delivers precise, wear-resistant adjustment.
Toroidal Winding
Uniform flux distribution for low noise and compact size.
Wide Capacity Range
From 0.5 kVA lab units to 30 kVA industrial regulators.
FAQ - Variable Transformers
What is the difference between a variable transformer and a voltage regulator?
Can it run at full load continuously?
Should I choose single-phase or three-phase?
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