| Brand | ROCKWILL |
| Model NO. | Low-Loss Three-Phase Photovoltaic Isolation Transformer |
| Rated frequency | 50/60Hz |
| Rated capacity | 1250kVA |
| Phases | Three-phase |
| Series | SGG |
Product Overview：
For many years, our company has specialized in manufacturing SD/SG(YSD) series single-phase and three-phase dry-type transformers dedicated to mechanical equipment, with capacities ranging from 1KVA to 3000KVA. Developed by referencing the latest similar products from Siemens, our SG series three-phase dry-type transformers not only provide voltage transformation in the power grid but also isolate third harmonics from the grid to equipment, reducing heat generation in machines and extending the service life of insulating materials. They are particularly suitable for imported equipment (380V input → 220V output, 380V input → any voltage output, 220V input → any voltage output) with specifications from 1KVA to 3000KVA.
Our SG and DG series dry-type isolation transformers are widely applicable to various power supply scenarios with AC 50-60HZ and input/output voltages not exceeding 3000V. All parameters, including input/output voltage levels, connection groups, tap positions, winding capacity distribution, secondary winding configurations, and whether a casing is required, are meticulously designed and manufactured according to user requirements.
Material Configuration Description of Transformer：
Transformers serve as the main components of various power supplies and electrical equipment. Isolation transformers consist of cylindrical windings and laminated cores, where the core is stacked with brand-new high-quality high-silicon silicon steel sheets using fully mitered joints. Our company employs advanced manufacturing processes, including imported Max high-speed automatic winding machines and a full set of vacuum pressure impregnation (VPI) equipment. The windings are formed using the skeletonless full-series winding method, and the transformers undergo vacuum impregnation to achieve insulation classes of F (155℃) or H (180℃).The input and output voltages of the transformer can be designed according to customer requirements, available in various specifications such as single-phase, three-phase, or multiple-way input/output configurations.
Core：Made of brand-new high-quality high-silicon silicon steel sheets, mainly with materials of 0.35mm thick H18, H14, H12, and Z11 high-quality silicon steel sheets. We select the most suitable material based on customer requirements and usage conditions to optimize the transformer's performance design. (Conventional material: brand-new high-quality silicon steel sheets).
Wire：Using PEW, UEW, EIW, SEIW, FEAI enameled wires and glass fiber-covered wires, with temperature resistance grades of F (155℃), H (180℃), HC (200℃), and C (220℃). (Conventional temperature resistance grade: H grade, 180℃).
Insulating Materials：Adopting high-temperature resistant insulating paper as the insulating material, which has multiple properties of high-temperature insulation, flame retardancy, and moisture resistance.
Insulating Material Terminal Blocks
Iron Feet：Mainly made of CNC bent cold-rolled steel plates, with environmentally friendly electroplating options such as multicolor plating (golden yellow), blue zinc (silver white), white zinc (ivory white), and surface anodizing (black).
Technical data：
Product Operating Conditions:
-
Strange Devices on Transmission Lines: 5 Little-Known Practical Functions（1）1 Aviation Warning SpheresAviation warning spheres, also known as reflective safety spheres, are used on overhead transmission lines near airports, especially on extra-high-voltage (above 220kV) lines and river-crossing transmission lines. Highly visible aviation marker spheres (aviation warning spheres) must be installed along the lines to provide warning signals.The aviation marker sphere (aviation warning sphere) has a diameter of ф=600mm. The sphere can be manufactured in various bright coloLeon09/04/2025 -
Transmission LineIn transmission lines, a "π" connection involves breaking the original line from Substation A to Substation B and inserting Substation C, forming a "π" configuration. After the "π" connection, the original single line is divided into two independent transmission lines. Following the "π" connection, Substations B and C may both be powered by Substation A (in this case, Substation C receives power via a feeder from Substation B's busbar, or possibly from another voltage point within Substation B);Encyclopedia09/04/2025 -
What are the principles of forced re-energization of transmission lines?Principles of Forced Re-energization of Transmission LinesRegulations for Forced Re-energization of Transmission Lines Correctly select the forced re-energization end of the line. If necessary, change the connection configuration before forced re-energization, taking into account the reduction of short-circuit capacity and its impact on grid stability. There must be a transformer with its neutral point directly grounded on the busbar at the forced re-energization end. Pay attention to the impactEdwiin09/04/2025 -
Analysis of Accident Handling in Transmission LinesAnalysis of Transmission Line Fault HandlingAs a fundamental component of the power grid, transmission lines are widely distributed and numerous, often exposed to diverse geographical and climatic conditions, making them highly susceptible to faults. Common causes include overvoltage, pollution flashover, insulation damage, tree encroachment, and external damage. Line tripping is one of the most frequent faults in power plant and substation operations, with fault types including single-phase-to-Leon09/04/2025 -
The difference between transmission and distribution linesTransmission lines and distribution lines are both used to carry electrical power from one location to another. However, they differ significantly in key aspects such as primary function, voltage levels, phase configuration, and conductor placement. These differences are essential for understanding their distinct roles in the power system.The Difference Between Transmission and Distribution Line is given below in the tabulated form.Electricity generation is a critical component of the power systEdwiin09/04/2025 -
Ensuring Reliability: A Deep Dive into Transformer MaintenanceIntroductionElectric transformers are the backbone of modern power distribution systems, silently enabling the reliable delivery of electricity to homes, businesses, and industries. As these critical assets age and the demand for uninterrupted power grows, the importance of diligent transformer maintenance has never been greater. This essay explores the essential role of transformer maintenance, highlighting the value of proactive care, the impact of advanced diagnostic technologies, and the traVziman09/03/2025
-
Intelligent Operation Solution for 12kV Vacuum Circuit Breakers: Integrating Real-time Monitoring & Lifetime OptimizationⅠ. Equipment Operation & MaintenanceIntelligent Monitoring System IntegrationMulti-parameter Real-time Monitoring: Embedded sensors (temperature, displacement, Hall effect current sensors) track contact temperature rise, mechanical characteristics (opening/closing speed, overtravel), coil current, and partial discharge signals. Data undergoes preprocessing via edge computing prior to cloud upload.Lifetime Prediction Model: Dynamically evaluates remaining lifespan using electrical wear dataRockwill06/10/2025 -
SF6 Circuit Breaker Solutions for Outdoor Installation (Anti-Pollution & Seismic Resistance)I.Core Challenges in Outdoor InstallationIn high-voltage transmission and distribution systems, SF6 circuit breakers are exposed to complex outdoor environments for extended periods, facing the following critical issues:Pollution & Insulation DegradationDust, salt fog, and industrial pollutants in outdoor environments easily adhere to equipment surfaces. In coastal or industrial areas, pollution levels may reach Class IV, resulting in insufficient creepage distance and triggering flashoRockwill05/12/2025
