10kV ZGS Combined Transformer
Case Description
Structural Features
The ZGS series combined transformer (commonly referred to as the “American-style transformer”) is used in 12 kV ring-network power supply, dual-source power supply, or terminal power supply systems as a complete set of equipment for transformation, distribution, metering, compensation, control, and protection. In addition to the transformer itself, the high-voltage side of the substation is equipped with a four-position (or two-position) load switch, backup protective fuses, and plug-in fuses; while the low-voltage side can be fitted, according to customer requirements, with control devices, distribution apparatus, compensation equipment, and metering instruments, among others.
This product incorporates the latest advanced technologies from abroad and has been developed in light of domestic conditions; the transformers used are of the S11-M and S13M series. The entire unit features a compact footprint, simple installation, low noise, low losses, comprehensive protection, easy maintenance, and excellent cost-effectiveness, making it suitable for use in new residential communities, green belts, parks, stations, docks, hotels, construction sites, airports, and other similar locations.
Product Model and Its Meaning

Structural Features
Fully sealed, fully insulated design; compact footprint; no insulation clearances required; reliably ensures personal safety.
Can be used for ring network and terminal power supply modes.
Adopting a full-range dual-power-supply protection scheme that combines dual-sensitive fuses with backup fuses significantly reduces operating costs.
The enclosure features corrosion-resistant design and powder-coating, making it suitable for a wide range of harsh environments.
The transformer has low losses and strong overload capability.
Terms of Use
Altitude not exceeding 1,000 m;
Ambient temperature: maximum +40°C, minimum -25°C
The highest daily average temperature is 35°C, and the highest annual average temperature is 20°C.
Wind speed does not exceed 34 m/s;
The relative humidity of the air shall not exceed 95% (at 25°C), and the monthly average shall not exceed 90%.
The ground slope shall not exceed 5°; the horizontal seismic acceleration shall not exceed 0.3 m/s².
The installation location shall be free from fire hazards, explosion risks, chemical corrosion, and severe vibration.
Installed on a cement platform or other flat, solid surface: oil-immersed and self-cooled.
Implementation Standard
IEC 1330 Prefabricated High-Voltage/Low-Voltage Substations
GB/T 17467 Prefabricated High-Voltage/Low-Voltage Substations
DLIT 537 Guidelines for the Selection of Prefabricated High- and Low-Voltage Substations
JB/T 10217 Combined Transformer
Ordering Instructions
Equipment Operating Environment
Transformer technical parameters, including transformer capacity, tap range, voltage levels, connection group, impedance, and loss levels; high-voltage circuit technical requirements, including the number of circuits and the cross-sectional area of high-voltage cables:
Technical requirements for low-voltage circuits, including the number of incoming cables per phase and the type of low-voltage incoming switchgear.
Other technical requirements.
Technical Specifications
Recognition Result
| Unit Name | Project | Unit | Parameters | ||
| High-voltage unit | Rated frequency | Hertz | 50 | ||
| Rated voltage | KV | 6 | 10 | ||
| Maximum operating voltage | KV | 7.2 | 11.5 | ||
| Power-frequency withstand voltage to ground and between phases/isolation breaks | KV | 25 | 35 | ||
| Lightning Impulse Voltage to Ground and Between Phases/Isolation Gaps | KV | 60/65 | 75/85 | ||
| Rated current | A | 400/630 | |||
| Rated short-time withstand current | KA | 12.5(2s) | 16(2s) | ||
| Rated Peak Withstand Current | KA | 31.5 | 40 | ||
| Low-voltage unit | Rated voltage | KV | 0.4 | ||
| Rated current of the main circuit | A | 50~ 2500 | |||
| Rated short-time withstand current | KA | 12.5 | |||
| Rated Peak Withstand Current | KA | 30 | 63 | 110 | |
| Branch current | A | 10 ~ 800 | |||
| Number of branch lines | Road | 1 to 12 | |||
| Compensation capacity | kVar | 0~360 | |||
| Transformer Unit | Rated capacity | kVA | 30~ 500 | 630~ 1600 | |
| Impedance Voltage | % | 4 | 4.5 | ||
| Tap range | ±2 × 2.5% ±5% | ||||
| Connection Group | Yyn0/Dyn11 | ||||
Basic Plan

Character-shaped reference foundation drawing
3
Note:
1. The pedestal is located on higher ground, with outward drainage around its perimeter and a level surface, ensuring uniform load distribution for the packaged transformer.
2. The inner and outer walls, as well as the pedestal platform, shall be plastered with 1:2 cement mortar to a thickness of 20 mm.
3. The bottom of the cable compartment shall be sloped toward the drainage trough to prevent water accumulation.
4. The foundation construction method shall comply with the relevant provisions of JGJ 16 “Technical Code for Electrical Design of Buildings.”
5. This drawing depicts the foundation layout for a “pin”-shaped structural configuration; foundations for other structural configurations will be provided separately by our factory during production.
Get a Quote
Please note: Kindly provide your mobile phone number and email address, and our dedicated staff will contact you as soon as possible!