ZGS Integrated Transformer Substation (Pad-Mounted Type)
North American-Style Combined Transformer with Load Break Switch & Protection Fuse
The ZGS series integrated transformer substation is a compact, pad-mounted unit that combines a distribution transformer, a load break switch, and protection fuses into a fully enclosed system. Designed according to North American standards, it offers a safe, weatherproof, and tamper-resistant solution for urban, industrial, and residential power distribution at 10–35kV.
ZGS units are ideal for projects that require low-profile, ground-level installation and front-access operation, especially in outdoor locations without substation buildings.
🧩 Product Overview
Rated Voltage: 10kV / 11kV / 33kV
Rated Capacity: 50–1600 kVA
Structure: HV chamber + oil-immersed transformer + LV chamber
Standards: ANSI / IEEE C57, IEC 60076, GB/T 17467-2020
Protection Options: Bay-o-net fuse, ELSP, T-oil switch
Cooling Type: ONAN (natural oil-air cooling)
Insulation: Mineral oil or FR3 eco-friendly oil
🌍 Application Scenarios
Urban residential power distribution networks
Prefabricated substations for shopping centers, office parks
Medium voltage transformer connection in wind/solar projects
Industrial plants with outdoor transformer placement
Replacements for pole-mounted transformers in compact areas
ZGS substations are widely used in North America, Southeast Asia, and the Middle East for their sealed structure and simplified site construction.
🔧 Key Features
Fully sealed, oil-immersed transformer with integrated HV & LV terminals
Compact footprint: all components housed in a single tamper-proof enclosure
Safe front access: all operations and fuse replacement from one side
High environmental resistance: suitable for -40°C to +50°C environments
Arc-proof design: optional with arc suppression channels
Corrosion-resistant finish: hot-dip galvanized and powder-coated steel cabinet
📊 Technical Parameters
| Parameter | Specification |
|---|---|
| Rated Voltage | 10 / 11 / 33kV |
| Rated Capacity | 50–1600 kVA |
| High Voltage Configuration | Load break switch + fuse |
| Low Voltage Output | 0.4kV (3-phase, 4-wire) |
| Cooling Method | ONAN |
| Frequency | 50Hz / 60Hz |
| Vector Group | Dyn11 / Yyn0 |
| Impedance Voltage | 4% / 6% |
| Protection Level | IP54 (cabinet), IP00 (transformer) |
| Temperature Rise Limit | ≤60K (winding), ≤55K (oil) |
📦 Optional Configurations
Ring Main Unit (RMU) integration for looped HV input
SF6-free switchgear or solid insulation LBS
Internal arc fault protection
Smart sensors for oil temperature, pressure, and current monitoring
Cable compartments with CT, PT, metering panel
❓ Frequently Asked Questions
• Is the ZGS substation oil-insulated or dry-type?
Standard ZGS is oil-immersed, but dry-type versions can be offered on request.
• Can it be installed in coastal or humid zones?
Yes. The enclosure is corrosion-resistant and sealed; polymer bushings can be selected for higher pollution classes.
• Does it support dual HV inputs (looped network)?
Yes. It can be configured with dual LBS or RMU inside the HV chamber.
• What protection does the transformer have?
It typically includes a bayonet fuse + ELSP backup fuse, optionally an oil temperature relay, and a pressure relief device.
• How does ZGS compare to a European-style compact substation?
ZGS is front-access and pad-mounted, with an oil tank integrated, while the European type is often side-access and modular.
📞 Contact for Drawings or Technical Support
Need assistance selecting the right ZGS unit for your project?
Contact our transformer engineering team:
Thor – Substation Equipment Engineer
📞 Tel: +86-0577-62788197
📱 WhatsApp: +86 159 5777 0984
📧 Email: thor@weishoelec.com













