ANSI/IEEE Compliant Pad-Mounted Substations & Transformers
Pad-mounted substations and compartmented transformers provide safe, space-efficient power distribution for underground electrical networks in residential, commercial, industrial, and renewable energy applications. Built in compliance with ANSI/IEEE C57.12.28, CSA, and IEC standards, these tamper-resistant, weatherproof outdoor assemblies integrate high-voltage switching, overload protection, transformer cores, and low-voltage distribution within a single secure enclosure.
-
![HV Prefabricated Substation]()
HV Prefabricated SubstationThe HV Prefabricated Substation is an integrated prefabricated device from Yuanzhuo Electrical Equipment. We designed it for high-voltage distribution applications.view more -
![American Substation]()
American SubstationThe American Substation from Yuanzhuo Electrical Equipment combines American prefabricated technology with local distribution needs. We built it with our mature manufacturing experience in...view more -
![Landscape-Type Transformer Substation]()
Landscape-Type Transformer SubstationThe Landscape-Type Transformer Substation is a new integrated distribution device from Yuanzhuo Electrical Equipment. We designed it for high-end buildings, commercial complexes, and municipal...view more -
![Bus Plug-in Box]()
Bus Plug-in BoxA bus plug-in box is the tap-off unit that connects outgoing circuits to a busway system. It plugs directly onto the bus duct at factory-made tap-off points and houses the protective device —...view more -
![Compact Bus Duct]()
Compact Bus DuctA compact bus duct, also known as a busway or busbar trunking system, is a prefabricated enclosed conductor system used to transmit large currents between switchgear, transformers and load...view more -
![Fire Emergency Power Cabinet]()
Fire Emergency Power CabinetThe fire emergency power cabinet is a dedicated power distribution unit for first-level emergency loads such as fire pumps, emergency fans, smoke exhaust systems and other life-safety equipment....view more -
![LV Fixed-separated Distribution Cabinet]()
LV Fixed-separated Distribution CabinetThe LV fixed-separated distribution cabinet is a fixed-type low-voltage switchgear for standard distribution applications that do not require frequent module replacement. The enclosure is a welded...view more -
![LV Draw-out Distribution Cabinet]()
LV Draw-out Distribution CabinetThe LV draw-out distribution cabinet is a modular low-voltage switchgear for applications where power supply continuity and quick maintenance are priorities. Built in the MNS, GCS and GCK series,...view more -
![Indoor AC Metal-clad Withdrawable Switchgear]()
Indoor AC Metal-clad Withdrawable SwitchgearThe indoor AC metal-clad withdrawable switchgear is a medium-voltage main distribution panel for substations and industrial distribution rooms where safe, maintainable power distribution is...view more -
![Outdoor HV & LV Switchgear Cabinet]()
Outdoor HV & LV Switchgear CabinetAn outdoor HV & LV switchgear cabinet is a complete power distribution unit engineered for outdoor installation, combining the high-voltage incoming section and low-voltage outgoing feeder...view more -
![LV Prefabricated Substation]()
LV Prefabricated SubstationThe LV Prefabricated Substation is an integrated prefabricated device from Yuanzhuo Electrical Equipment. We designed it for low-voltage distribution applications. We built it with our core...view more
Product Series
Single-Phase Loop/Radial Feed Pad-Mounted Transformers
Voltage Rating: Primary 2.4 kV to 34.5 kV | Secondary 120/240 V
Capacity Range: 10 kVA to 167 kVA
Configuration: Loop feed or radial feed configurations with dead-front high-voltage bushings.
Primary Use: Underground residential distribution (URD) networks and small commercial loads requiring compact ground-level installation.
Three-Phase Compartmentalized Pad-Mounted Substations
Voltage Rating: Primary 4.16 kV to 35 kV | Secondary 208Y/120 V, 480Y/277 V, 600 V
Capacity Range: 45 kVA to 5000 kVA
Compartment Layout: High-voltage and low-voltage cable compartments separated by metal barrier partitions with dual-door locking mechanisms.
Primary Use: Commercial complexes, industrial manufacturing facilities, institutional campuses, and infrastructure projects.
Solar PV & Renewable Energy Pad-Mounted Step-Up Transformers
System Voltage: Up to 38 kV primary | 600 V to 800 V inverter input
Capacity Range: 500 kVA to 6300 kVA
Fluid Options: FR3 natural ester synthetic fluid (Class K high flashpoint) or high-grade mineral oil.
Primary Use: Utility-scale solar arrays, wind power collection systems, and battery energy storage installations (BESS).
Specifications & Configuration
|
Pad-Mounted Transformer Technical Parameters |
|
|
Parameter |
Specification |
|
Rated Capacity |
45 kVA / 75 kVA / 112.5 kVA / 150 kVA / 300 kVA / 500 kVA / 750 kVA / 1000 kVA / 1500 kVA / 2000 kVA / 2500 kVA / 3750 kVA / 5000 kVA |
|
Primary Voltage (HV) |
4.16 kV / 7.2 kV / 12.47 kV / 13.2 kV / 13.8 kV / 22.9 kV / 34.5 kV; Delta or Wye connection |
|
Secondary Voltage (LV) |
208Y/120 V / 480Y/277 V / 240 V / 600 V |
|
Frequency |
50 Hz / 60 Hz |
|
Temperature Rise |
55°C / 65°C / 55/65°C dual rating |
|
Fluid Insulation Type |
Mineral Oil (Class O, 140°C flash point) or FR3 Natural Ester Fluid (Class K, >300°C fire point) |
|
Enclosure Security Standard |
IEEE C57.12.28 (Tamper Resistance) and IEEE C57.12.29 (Coastal Environment Finish) |
|
Enclosure Ingress Protection |
IP54 / IP55 / NEMA 3R / NEMA 4X |
|
High-Voltage Bushings |
200 A bushing wells / inserts (Loadbreak) or 600 A / 1250 A Deadbreak bushings |
|
Overcurrent Protection |
Bay-O-Net expulsion fuses paired with partial-range current-limiting fuses (SL Fuse) |
|
Switching |
Integrated 2-position or 4-position oil-immersed load-break switch; V-blade / T-blade |
Standard Mechanical & Electrical Accessories
De-energized tap changer (5-position: Nom, +/- 2 x 2.5%)
Automatic pressure relief valve with mechanical indication
Liquid level gauge, dial-type thermometer, and pressure/vacuum gauge
Drain valve with sampling device (1 inch NPT)
Penta-head lock bolt with captive padlocking security latch
Tank grounding pads (copper-faced or stainless steel)
Primary Applications
Underground Residential Distribution (URD):
Ground-level power distribution replacing overhead lines in urban and suburban developments.
01
Commercial Buildings & Shopping Centers:
Safe outdoor power step-down adjacent to structures without requiring internal electrical vaults.
02
Industrial Plants & Logistics Hubs:
Dedicated transformer power for heavy machinery, automated warehousing, and process manufacturing.
03
Renewable Energy & Microgrids:
Direct step-up connection for solar central inverters, wind generator strings, and energy storage enclosures.
04
Customization & OEM Capabilities
Cabinet Construction:
Heavy-gauge cold-rolled steel, 304 stainless steel, or 316L marine-grade stainless steel for severe atmospheric environments.
Custom Voltage Taps & Dual Voltage Ratings:
Dual primary voltage configurations (e.g., 7200 x 14400V) selectable via an internal switch.
Protection Integration:
Factory integration of surge arresters (under-oil or elbow arresters), low-voltage molded case circuit breakers (MCCB), current transformers (CT), and potential transformers (PT) for revenue metering.
Special Coatings & Colors:
Munsell Green (7.5GY3.2/1.5), ANSI 61 Gray, ANSI 70 Gray, or custom RAL powder coating with multi-stage zinc-phosphate pretreatment matching 1,000-hour salt spray endurance per ASTM B117.
Testing & Quality Control
Every unit undergoes 100% factory routine testing prior to dispatch in accordance with IEEE C57.12.00, ISO 9001, and ISO 14001 quality systems:
Dielectric Tests: Applied voltage test (power frequency withstand) and induced voltage test.
Lightning Impulse Withstand Test: Full-wave and chopped-wave impulse insulation validation (BIL up to 200 kV).
Winding & Loss Measurement: Resistance measurement, voltage ratio, phase relation checks, no-load loss, and load loss validation against DOE 2016 energy efficiency standards.
Tank Leakage Test: Positive pressure leak test (45 kPa) performed for 24 hours on all welded oil tanks.
Partial Discharge Test: PD level maintained below 10 pC for dry-type and gas-filled units at 1.2 Un.
Mechanical Security Verification: IEEE C57.12.28 pry bar, pull test, and hinge endurance tests to guarantee tamper-proof public safety.
Export Packaging: Vacuum VCI corrosion-inhibitor foil wrapping, corner protection pads, and heavy-duty ISPM 15 heat-treated wooden crates or palletized skid mounting secured with steel strapping.
Technical Documentation Package Supplied with Shipment:
Factory Acceptance Test (FAT) Report & Quality Certificate
As-Built Dimension Drawings, Wiring Schematics, and 3D STEP/CAD Models
Transformer Nameplate Drawing and Component Manuals
Installation, Operation, and Maintenance (IOM) Manual
Logistics Support: Transport handled via FCL, Open Top, or Flat Rack containers under FOB, CIF, or DDP delivery terms.
FAQ
Request a Quote
To receive a detailed technical proposal, dimensional drawing, and commercial quotation within 24 hours, please submit your project specifications to our engineering team:
System Type: Single-Phase or Three-Phase Pad-Mounted Substation / Transformer.
Electrical Specifications: KVA rating, Primary Voltage (kV) with BIL, Secondary Voltage (V), Vector Group, and Frequency.
Feed Configuration: Loop Feed or Radial Feed | Dead Front or Live Front.
Enclosure Material & Fluid Type: Steel / 304SS / 316SS | Mineral Oil or FR3 Natural Ester Fluid.
Single-Line Diagram (SLD) or Tender Technical Specification Package.
Email your project drawings directly to our engineering team: [Sales / Engineering Email]
We're well-known as one of the leading pad mounted substation manufacturers and suppliers in China. We warmly welcome you to wholesale high quality pad mounted substation at competitive price from our factory. If you have any enquiry about cooperation, please feel free to email us.
Landscape Type Transformer Substation, HV Prefabricated Substation, American Substation
