SG-1000VA
3-Phase Low Voltage Dry-Type Autotransformer (1kVA to 500kVA) Designed for maximum efficiency and cost-effective voltage adjustment, our 3-phase low voltage autotransformer converts utility supply voltages (e.g., 380V/400V/480V) to match imported machinery requirements (e.g., 200V/220V). Featuring a compact dry-type structure, high permeability silicon steel cores, and over 98% operating efficiency, it is the ideal choice for CNC machines, automation lines, and industrial motors. Voltage Options: Primary 380V/400V/415V/480V to Secondary 200V/220V/208V (Customizable) Key Advantages: Ultra-high efficiency (≥98%), compact footprint, lower cost, quiet operation Service: Factory Direct | Custom Taps & Enclosures | Fast Delivery
Ultra-High Energy Efficiency (≥98%): Optimized magnetic circuit design and low-loss core materials drastically lower operating losses and heat generation, reducing electricity costs.
Cost-Effective & Space-Saving: Shares a common winding, making it 20%-40% smaller and lighter than an equivalent isolation transformer while offering superior economical value.
Multi-Voltage Tap Customization: Tailored input and output taps accommodate various global grid voltages (e.g., Input 380V/415V/480V -> Output 200V/208V/220V).
Strong Overload Capacity: Engineered with high-thermal-class insulation (Class F / Class H) to handle short-time motor starting currents and heavy industrial loads.
Low Noise & Quiet Operation: Noise below 50dB.
The 3-Phase Low Voltage Dry-Type Autotransformer provides a reliable, economic, and highly efficient solution for stepping up or stepping down AC voltage in 3-phase power distribution networks. Unlike traditional double-wound isolation transformers, an autotransformer utilizes a shared winding design, resulting in significantly reduced size, lower weight, minimized energy loss, and excellent cost efficiency.
Our autotransformers are specifically designed to bridge the voltage gap between local utility grids and imported industrial machinery (such as Japanese, European, or North American equipment). Fully compliant with IEC 60076 and ISO standards, they deliver continuous, stable power to high-demand industrial automation systems.
| Parameter | Specifications / Range |
| Product Model | 3-Phase Low Voltage Dry-Type Autotransformer |
| Rated Capacity | 1 kVA – 3000 kVA (Customizable) |
| Primary Voltage (Input) | 380V, 400V, 415V, 440V, 480V (Selectable / Multi-tap) |
| Secondary Voltage (Output) | 200V, 208V, 220V, 380V (Selectable / Multi-tap) |
| Frequency | 50 Hz / 60 Hz |
| Winding Material | High-Grade Copper or Aluminum |
| Vector Group / Connection | Y / Star (Auto-connection with neutral) |
| Efficiency | ≥ 98% |
| Insulation Class | Class F (Standard) / Class H (Optional) |
| Cooling Method | Air Natural (AN) / Air Force (AF with cooling fans) |
| Enclosure Protection | IP00 (Open type), IP20 / IP23 Metal Cabinet |
| Compliance Standards | IEC 60076 and ISO9001 |
| Model | Size | Weight |
| SG-2KVA | 200*180*200mm | 15kg |
| SG-3KVA | 300*250*280mm | 20kg |
| SG-10KVA | 355*305*355mm | 40kg |
| SG-15KVA | 400*350*430mm | 65kg |
| SG-20KVA | 500*400*470mm | 75kg |
| SG-30KVA | 550*450*550mm | 120kg |
| SG-40KVA | 550*450*550mm | 130kg |
| SG-50KVA | 600*500*580mm | 140kg |
| SG-60KVA | 600*500*580mm | 150kg |
| SG-80KVA | 650*550*710mm | 180kg |
| SG-100KVA | 650*550*710mm | 210kg |
The weight and dimensions are for reference only, please refer to the actual situation.
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Our 3-phase autotransformers are widely used across diverse industrial sectors requiring direct voltage adjustment:
Imported CNC Machinery: Lathes, milling machines, laser cutters, and machining centers.
Industrial Automation: SMT surface mount equipment, PCB manufacturing lines, and robotic arms.
Motor & Pump Drives: Step-down voltage starting for large AC induction motors, fans, and compressors.
Commercial Power Systems: HVAC systems, printing presses, and plastic injection molding machinery.
Q1: When should I choose an Autotransformer instead of an Isolation Transformer?
A: You should choose an Autotransformer if you simply need to convert line voltage (e.g., from 380V to 220V for imported machinery) and do not require complete electrical/galvanic isolation between the primary and secondary circuits. It is much more compact, highly efficient, and cost-effective.
Q2: Can this autotransformer be built into our existing control cabinet?
A: Yes, we supply open-type (IP00) autotransformers specifically designed for integration inside customer control panels, as well as standalone enclosed units (IP20/IP23) for floor mounting.
Q3: Do you support dual or multiple output voltages on a single autotransformer?
A: Absolutely. We can engineer multi-tap output terminals (for example, 380V input to both 220V and 200V outputs) according to your electrical schematics.