Industry Overview
Mining operations present some of the most demanding electrical environments in industry. From deep underground shafts where explosive gases accumulate, to remote open-pit mines in extreme climates, power distribution systems must perform reliably under conditions that would disable conventional equipment. Electrical failures in mining carry consequences far beyond production loss — they threaten human life.
Harsh Environment
Dust, moisture, vibration, and corrosive atmospheres demand equipment built beyond standard industrial ratings.
Remote Locations
Mines operate far from grid infrastructure, requiring robust autonomous power systems with minimal maintenance needs.
Safety Critical
Explosive gas and dust atmospheres require ATEX-certified, flameproof equipment — compliance is non-negotiable.
Key Challenges
Fine particulate matter penetrates conventional enclosures, causing tracking, insulation breakdown, and contact failure. IP55+ is the minimum requirement.
Equipment must operate from -40°C in high-altitude surface mines to +55°C in deep underground workings with limited ventilation.
Blasting, heavy machinery, and conveyor systems generate continuous vibration. Equipment must withstand mechanical stress without loosening or failing.
Underground equipment may be kilometres from the shaft entrance. Maintenance windows are short; equipment must be exceptionally reliable and accessible.
Methane and coal dust create Group I explosive atmospheres. ATEX/IEC 60079 compliance with flameproof or increased-safety enclosures is mandatory.
Underground openings have fixed dimensions. Equipment must pass through drifts and shafts, often requiring compact or modular designs.
Our Solutions
⚡ Mine-Duty Transformers
Purpose-built for mining environments with ATEX-certified flameproof enclosures, dry-type or less-oil construction, and ratings from 100kVA to 50MVA. Designed for shaft transport and underground installation.
- • Group I ATEX certification (Ex d I / Ex e I)
- • IP55–IP65 protection as standard
- • Dry-type cast resin or less-oil designs
- • Temperature class T1–T4 available
🏗️ Compact Underground Substations
Integrated transformer-switchgear units engineered for mine shaft dimensions. Single-enclosure design eliminates external cabling, reduces installation time, and provides complete protection in Zone 1 and Zone 2 areas.
- • Transportable through standard drift openings
- • Combined HV/LV protection in one enclosure
- • Remote monitoring capability
- • Ratings up to 4000kVA at 6.6kV/3.3kV
🔥 Flameproof Switchgear
Medium-voltage and low-voltage switchgear in flameproof enclosures rated for Group I mining atmospheres. Vacuum circuit breakers with proven reliability under arduous duty cycles.
- • Ex d I flameproof certification
- • Vacuum interrupter technology
- • 3.3kV, 6.6kV, and 11kV ratings
- • Integrated protection relays
📊 Instrument Transformers
Current and voltage transformers for mining metering and protection, available in ATEX-certified designs for installation in hazardous zones. High accuracy class ensures reliable protection relay operation.
- • ATEX Group I certified options
- • Accuracy class 0.2 / 0.5 / 0.2S
- • Cast resin insulated, maintenance-free
- • Designed for mining duty cycles
Product Showcase
Power Transformers
Mine-duty, dry-type, and oil-immersed transformers rated up to 50MVA with ATEX certification.
View Transformers →Flameproof Switchgear
MV and LV switchgear in Ex d I enclosures for Zone 0/1 mining atmospheres.
View Switchgear →Instrument Transformers
CTs and VTs for mining protection and metering, ATEX-certified for hazardous zones.
View Instrument Transformers →Technical Specifications
| Parameter | Standard Duty | Heavy Duty | Extreme Duty |
|---|---|---|---|
| Protection Rating | IP54 | IP55 | IP65 / IP67 |
| Ambient Temperature | -25°C to +40°C | -40°C to +55°C | -50°C to +60°C |
| ATEX Classification | Ex e I (Zone 2) | Ex d I (Zone 1) | Ex d I (Zone 0) |
| Seismic Qualification | 0.2g | 0.3g | 0.5g |
| Vibration Level | IEC 60068-2-6 | IEC 60068-2-6 enhanced | IEC 60068-2-27 shock |
| Altitude Derating | Up to 1000m | Up to 3000m | Up to 5000m |
| Insulation Class | Class F (155°C) | Class H (180°C) | Class C (220°C) |
Standards & Compliance
Explosion Protection
- IEC 60079 — Explosive atmospheres equipment
- EN 60079 — European ATEX harmonized standard
- ATEX Directive 2014/34/EU — EU certification
- IEC 60079-1 — Flameproof enclosures (Ex d)
- IEC 60079-7 — Increased safety (Ex e)
Equipment Standards
- IEC 60076 — Power transformers
- IEC 62271 — High-voltage switchgear
- IEC 61869 — Instrument transformers
- ISO 9001 — Quality management system
- IEC 60068-2 — Environmental testing
Case Study
50MVA Underground Substation — Kamoa Copper Mine, Democratic Republic of Congo
When a major copper mining operation in Central Africa required reliable power distribution for a new underground block cave operation at 1,200m depth, Ziyao Power delivered a complete power solution under extreme schedule pressure. The project involved designing, manufacturing, and commissioning flameproof transformers and switchgear rated for Group I explosive atmospheres in a high-temperature, high-humidity environment with limited shaft access.
The solution comprised two 25MVA dry-type transformers in flameproof enclosures, 6.6kV vacuum switchgear with integrated protection, and a complete SCADA monitoring system. All equipment was designed for transport through the 4.0m × 3.5m shaft opening and assembled underground. The system achieved zero-downtime commissioning and has operated continuously since energization in Q2 2025.
Why Choose Ziyao Power
Technical Support
Deep expertise in mining power systems across copper, gold, coal, and platinum operations worldwide.
ATEX Certified
Full ATEX Group I certification for flameproof and increased-safety equipment in mining atmospheres.
Custom Engineering
Every mine is different. We engineer solutions for your specific conditions — altitude, climate, shaft dimensions, and duty cycles.
Global Delivery
Equipment delivered to mines across Africa, South America, Central Asia, and Southeast Asia with full logistics support.
Frequently Asked Questions
What makes a transformer suitable for underground mining?▼
What is ATEX certification and why is it required for mining equipment?▼
What IP rating is required for mining electrical equipment?▼
How are compact substations designed for underground mines?▼
What voltage levels are common in mining power distribution?▼
Can Ziyao Power customize equipment for specific mine conditions?▼
What standards govern mining electrical equipment?▼
What is the typical lead time for mining-grade transformers?▼
Ready to Power Your Mine?
Whether you're developing a new underground operation or upgrading an existing power system, our mining specialists will design a solution engineered for your conditions.