Mini-Substation

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Product Overview

Mini-Substation

Low-voltage rated voltage	0.4 kV; Custom 480 V etc. for export projects
Rated capacity	50 kVA - 2500 kVA
Power Supply Mode	Loop-feed type; Radial-feed type; Dual-power-supply type
Frequency	50 Hz; 60 Hz customizable for overseas projects
Cooling Type	Transformer: ONAN / ONAF;Cabinet: Natural ventilation + temperature-controlled forced-air cooling

High-voltage class	6 kV – 35 kV	Low-voltage rated voltage	0.4 kV; Custom 480 V etc. for export projects
Rated capacity	50 kVA – 2500 kVA	Power-supply mode	Loop-feed type; Radial-feed type; Dual-power-supply type
Frequency	50 Hz; 60 Hz customizable for overseas projects	Transformer vector group	Dyn11
Tap-changer	Off-circuit tap-changer ±2 × 2.5%	Cooling type	Transformer: ONAN / ONAF; Cabinet: Natural ventilation + temperature-controlled forced-air cooling
Enclosure protection rating	IP54; IP55 optional	Ambient operating temperature	-25 °C – +40 °C; High-temperature version up to +55 °C available
Insulation level	Matched with GB 1094 and IEC 62271-202 standards according to voltage class	Noise emission	Typical ≤65 dB(A) at 1 m
Thermal margin	≥20% thermal margin reserved for transformer-compartment ventilation	Service life	≥30 years under normal outdoor operating conditions
Anti-corrosion grade	C3, C4, C5, CX-H	Transformer type	Oil-immersed transformer; Dry-type transformer optional
High-voltage equipment	SF6 ring-main unit; Vacuum load switch; Vacuum circuit breaker; Current-limiting fuse; Surge arrester; Earthing switch	High-voltage supply mode	Loop-feed; Radial-feed; Dual-power supply
Low-voltage equipment	Air circuit breaker; Moulded-case circuit breaker; Protection relay; Metering; Reactive-power compensation	Communication protocol	Modbus-RTU / TCP; IEC 60870-5-104
Remote control	Three-remote-control functions	Auxiliary power	UPS auxiliary power supply optional
Interlock system	Electrical-mechanical five-anti interlock	Compartment structure	Three-compartment independent metal isolation
Layout	Vertical layout; Square layout	Ventilation	Independent ventilation ducts; Temperature-controlled forced-air cooling
Temperature monitoring	PT100 temperature sensors; Temperature controller; Over-temperature alarm and trip output	Dehumidification	Optional compartment dehumidification device
Typical model	YBW-12/0.4-1250 kVA loop-feed European-style prefabricated substation	Primary voltage	10 kV
Secondary voltage	0.4 kV	Installation	Outdoor pad-mount installation
Standards	IEC 62271-202; IEC 62271-1; IEC 61439-1/2; IEC 60076; GB/T 17467-2020; GB 1094; GB 1094.11; GB 7251	Seismic standard	IEEE 693 optional
Export compliance	RoHS; REACH; EPA 40 CFR Part 761	Factory testing	FAT; Routine tests; Type tests; Dielectric tests; Interlock-function tests; Protection verification
Spare-parts supply	Minimum 25-year spare-parts supply for key components	LCA documentation	Available upon request

Protection & Accessories

Reliable Protection System and Flexible Accessories

Our Pad Mounted Transformers are equipped with reliable protection devices and accessories to ensure safe operation in underground distribution systems and utility applications.

Standard Accessories

HV/LV Bushings

Reliable medium voltage connection with excellent insulation performance.

Oil Level Gauge

Easy monitoring of insulating oil level for maintenance.

Pressure Relief Device

Improves transformer safety under abnormal conditions.

Drain Valve

Convenient oil draining and maintenance operation.

Tap Changer

Off-circuit Tap Changer (OCTC), ±2 × 2.5%

Nameplate

Provides complete transformer rating and technical information.

Optional Accessories

Temperature Indicator

Monitors transformer operating temperature for reliability.

Remote Monitoring System

Supports smart grid and remote transformer condition monitoring.

Surge Arrester

Protects pad mounted transformers against lightning and voltage surges.

Key Features of Transformers

Key Benefits:

Enhanced operator and public safety
No exposed high-voltage components
Suitable for underground distribution systems
Reliable operation in outdoor environments

Key Benefits:

Weather-resistant construction
Corrosion-resistant surface treatment
Secure locking compartment
Suitable for public and utility applications

Key Benefits:

Space-saving installation
Low-profile outdoor design
Easy inspection and maintenance
Ideal alternative to overhead distribution systems

Available Configurations:

Loop feed distribution system
Radial feed distribution system
Dead-front cable connection
Customized MV and LV connection arrangements

Available protection and accessories include:

High voltage fuses
Current limiting fuses
Load break switches
Surge arresters
Pressure relief devices
Temperature monitoring systems

These protection solutions help ensure safe operation under different load and fault conditions.

Key Benefits:

Low no-load losses
High energy efficiency
Excellent thermal performance
Long operational lifetime

Manufacturing & Testing

Strict Quality Control and Transformer Testing

Every Pad Mounted Transformer undergoes comprehensive testing to ensure high reliability, safety and long service life according to international standards.

Routine Tests

Transformer Ratio Test

Ensures accurate voltage transformation performance.

Winding Resistance Test

Verifies winding quality and electrical performance.

No-Load Loss Test

Checks transformer core efficiency and energy performance.

No-Load Loss Test

Confirms transformer rated efficiency under operating conditions.

Impedance Test

Ensures correct electrical characteristics and system compatibility.

Dielectric Test

Verifies insulation strength and operational safety.

Special Tests

Temperature Rise Test

Validates thermal performance and cooling capability.

Lightning Impulse Test

Tests insulation capability against surge conditions.

Partial Discharge Test

Ensures insulation quality and long-term reliability.

Everything We Do Is At A High Standard

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WHAT WE DO

CTSS Transformer Applications and Solutions

We design and manufacture liquid-filled power transformers and distribution transformers for a wide range of applications, including solar power, data centers, industrial facilities, and utility systems. With experienced engineers and advanced manufacturing capabilities, we provide customized transformer solutions and complex winding designs to meet the specific electrical and performance requirements of each project.