1. Introduction to Halogen-Free Cable Technology

With voltage ratings from 3.6/6 kV to 12/20 kV, these cables are specifically engineered for heavy mobile mining equipment in opencast operations, providing reliable power transmission while meeting increasingly stringent environmental and safety regulations worldwide.

1.1 Cable Designation Explained

The designation “(N)TSCGEWÖU” indicates specific design characteristics:

• (N) – Design variant specification
• TSC – Trailing cable for heavy service applications
• GE – Integrated earth conductor system
• WÖU – Weather and environmentally resistant design for outdoor use

1.2 Why Halogen-Free Technology Matters

According to International Electrotechnical Commission (IEC) research, halogen-free cables significantly reduce casualty rates in fire incidents, making them increasingly mandatory in modern mining operations and enclosed spaces.

2. Purpose and Applications

2.1 Primary Purpose

The (N)TSCGEWÖU cable is engineered for flexible power transmission to heavy mobile mining equipment during continuous trailing operations. The halogen-free polyurethane construction makes it particularly suitable for:

• Operations requiring enhanced fire safety standards
• Environmentally sensitive mining sites
• Operations near populated areas with strict emission regulations
• Underground or semi-enclosed working environments
• International projects requiring global environmental certifications

2.2 Target Equipment

Designed for powering heavy mobile mining machinery including:

• Draglines: Large-scale excavating equipment with suspended bucket systems
• Electric Shovels: High-capacity loading machines for material handling
• Dredges: Underwater and wetland excavation equipment
• Rotary Drills: Blast hole drilling rigs and exploration equipment
• Bucket-Wheel Excavators: Continuous mining systems
• Mobile Crushers and Conveyors: Material processing equipment requiring flexible connections
• Stacker/Reclaimers: Bulk material handling systems

2.3 Operating Environments

The (N)TSCGEWÖU cable excels in challenging conditions:

2.4 Regulatory Compliance Applications

This halogen-free cable is essential for operations requiring compliance with:

• EU RoHS (Restriction of Hazardous Substances) directives
• ISO 14001 Environmental Management Systems
• LEED (Leadership in Energy and Environmental Design) certified facilities
• National mining safety regulations mandating low-smoke, zero-halogen cables
• Corporate sustainability and ESG (Environmental, Social, Governance) commitments

3. Key Characteristics and Advantages

3.1 Enhanced Mechanical Performance

3.2 Superior Electrical Design

• Voltage Range: 3.6/6 kV to 12/20 kV rated voltage with full range coverage
• Class 5 Conductors: Tinned copper for maximum flexibility (VDE 0295 / IEC 60228)
• Triple-Layer Semiconductive System: Conductor shield, inner and outer insulation shields
• Advanced Earth System: Tinned copper Class 5 earth conductors with semiconductive covering, split into 3 parts for enhanced protection
• 3GI3 Quality Insulation: Premium rubber compound per VDE 0207 Part 20

3.3 Exceptional Flexibility

The cable achieves outstanding flexibility through:

• Class 5 Conductor Construction: Fine-strand conductors for millions of bending cycles
• Polyurethane Sheaths: Superior flex-fatigue resistance compared to rubber
• Optimized Core Twisting: Engineered lay length for minimum bending stress
• Anti-Twist Element: Polyester braid prevents rotation and kinking

3.4 Enhanced Thermal Performance

3.5 Environmental Resistance

• Halogen-Free: IEC 60754-1 and IEC 60754-2 certified
• Flame Retardant: IEC 60332-1-2 compliant
• Oil Resistant: Superior to rubber in petroleum environments (IEC 60811-2-1)
• Ozone Resistant: Polyurethane maintains integrity in high-ozone conditions
• UV Resistant: Excellent resistance to solar degradation
• Weather Resistant: Indoor and outdoor application certified
• Abrasion Resistant: Polyurethane offers superior abrasion resistance

3.6 Polyurethane Sheath Advantages

4. Material Structure and Construction

The (N)TSCGEWÖU cable features advanced five-layer construction optimized for performance, safety, and environmental responsibility.

4.1 Complete Layer-by-Layer Construction

4.2 Advanced Earth Conductor System

The (N)TSCGEWÖU features an enhanced earth conductor design:

• Material: Tinned copper Class 5 stranded conductors for maximum flexibility
• Configuration: Three separate earth conductors split around the cable core
• Covering: Each earth conductor wrapped with semiconductive layer
• Advantages:
  • Superior ground fault protection from multiple paths
  • Enhanced screening against electromagnetic interference
  • Redundancy for critical safety applications
  • Better distribution of fault currents

4.3 Material Specifications

4.3.1 Conductor System

Tinned Copper Conductors (Class 5):

• Extremely fine stranding for maximum flexibility (VDE 0295 / IEC 60228)
• Tin coating provides corrosion resistance in humid environments
• Enhanced solderability for reliable terminations
• Suitable for millions of bending cycles without fatigue failure
• Available in conductor sizes from 25 mm² to 185 mm²

4.3.2 Insulation Materials

3GI3 Quality Rubber Compound (VDE 0207 Part 20):

• Excellent dielectric properties for voltages up to 12/20 kV
• Superior flexibility maintained across operating temperature range
• Resistance to electrical tracking and corona discharge
• Long-term aging stability under thermal stress
• Compatible with polyurethane sheaths for optimal bonding

4.3.3 Semiconductive System

The cable employs advanced triple-extrusion technology:

• Conductor shield, insulation, and insulation shield extruded simultaneously
• Perfect interface adhesion eliminates air voids
• Uniform electrical stress distribution prevents partial discharge
• Semiconductive tape separator over twisted cores provides additional protection
• Central filler with semiconductive properties maintains cable geometry

4.3.4 Halogen-Free Polyurethane Sheaths

Advanced Polyurethane Technology:

• Composition: Thermoplastic polyurethane (TPU) formulation
• Hardness: Optimized Shore A hardness for flexibility and protection
• Density: Lower than rubber (approximately 1.2 g/cm³ vs 1.4-1.5 g/cm³)
• Abrasion Resistance: Exceptional wear resistance exceeding rubber by factor of 5-10
• Chemical Structure: No chlorine, bromine, or fluorine compounds
• Fire Performance: Self-extinguishing with minimal smoke generation

5. Halogen-Free Polyurethane Technology

5.1 Understanding Halogen-Free Requirements

Halogen-free cables are defined by international standards as cables that emit minimal amounts of halogen acids and corrosive gases when exposed to fire.

What Are Halogens?

Halogens are a group of elements including:

• Chlorine (Cl): Found in PVC and chlorinated compounds
• Bromine (Br): Common in flame retardants
• Fluorine (F): Used in some high-temperature materials
• Iodine (I) and Astatine (At): Less common in cables

5.2 Hazards of Halogenated Cables in Fire

5.3 Halogen-Free Testing Standards

5.4 Polyurethane Material Advantages

5.4.1 Fire Safety Benefits

• Zero Halogen Emissions: No toxic halogen gases released during combustion
• Low Smoke Generation: Minimal smoke production maintains visibility
• Self-Extinguishing: Material stops burning when flame source removed
• Non-Corrosive: Fire residues don’t attack metal or electronic equipment
• Reduced Toxicity: Combustion products significantly less toxic than PVC

5.4.2 Mechanical Performance Benefits

5.4.3 Environmental Benefits

• Recyclability: Thermoplastic polyurethane can be mechanically recycled
• Reduced Environmental Impact: Manufacturing process has lower carbon footprint
• No Plasticizer Migration: Unlike PVC, doesn’t release plasticizers over time
• Longer Service Life: Reduced replacement frequency lowers overall environmental impact
• Compliance with Green Building Standards: Meets LEED and similar environmental certifications

5.5 When to Specify Halogen-Free Cables

Halogen-free cables are recommended or required for:

• Operations with stringent fire safety requirements
• Facilities with sensitive electronic equipment
• Projects requiring environmental certifications (LEED, ISO 14001)
• Public infrastructure and transportation systems
• Enclosed or semi-enclosed mining operations
• Applications where evacuation routes must remain clear during fire
• Regions with regulations mandating low-smoke, zero-halogen cables
• Corporate sustainability initiatives and ESG compliance

6. Compliance with Standards

6.1 Primary Design Standard

DIN VDE 0250 Part 813: “Power cables with rubber insulation for rated voltages up to and including 18/30 kV – Part 813: Flexible cables for special installations”

This German standard specifically addresses trailing cables for mining equipment and defines:

• Construction requirements for high-flexibility applications
• Minimum thickness for insulation and sheaths
• Testing protocols for mechanical and electrical performance
• Special requirements for reeling and trailing operations

6.2 Conductor Standards

• VDE 0295 (IEC 60228): Conductors of insulated cables – Class 5 specification for flexible conductors ensures maximum flexibility for continuous flexing applications

6.3 Material Standards

6.4 Electrical Performance Standards

• VDE 0298 Part 4: Current-carrying capacity calculations for power cables
• VDE 0298 Part 3: Minimum bending radius requirements for flexible installations
• IEC 60840: Power cables with extruded insulation and their accessories for rated voltages above 30 kV

6.5 Halogen-Free and Fire Performance Standards

6.6 Special Testing Requirements

The (N)TSCGEWÖU cable undergoes specialized testing:

• Reeling Test: Simulates continuous reeling and unreeling operations to verify mechanical durability
• Torsional Stress Test: Validates ±25°/m torsional stress tolerance
• Tensile Load Test: Confirms 20 N/mm² maximum tensile strength
• Flex Fatigue Test: Validates performance over millions of bending cycles
• Environmental Tests: Temperature cycling, UV exposure, ozone resistance

6.7 Certifications and Approvals

Cables manufactured to these standards typically carry:

• VDE Testing and Certification Institute approval mark
• TÜV (Technischer Überwachungsverein) product certification
• CE marking for European market compliance
• RoHS compliance for hazardous substance restrictions
• UL/CSA recognition for North American markets (where applicable)
• Mining authority approvals from relevant jurisdictions

7. Safety Thresholds and Operating Limits

7.1 Electrical Safety Parameters

7.2 Thermal Operating Limits

7.3 Enhanced Mechanical Limits

7.3.1 Tensile Stress Limits

Maximum Tensile Load: 20 N/mm² (referred to total phase conductor cross-section)

This represents a 33% increase over standard rubber-sheathed cables (15 N/mm²).

Example calculation for 3×95 mm² + 3×50/3E cable:

• Total phase conductor area: 3 × 95 mm² = 285 mm²
• Maximum permissible tensile force: 285 mm² × 20 N/mm² = 5,700 N
• Recommended working load: 50-60% of maximum = 2,850-3,420 N
• Comparison to rubber version: 285 × 15 = 4,275 N (25% lower capacity)

7.3.2 Torsional Stress Limits

Maximum Torsional Stress: ±25°/meter

This specification is critical for reeling applications:

• Allows for controlled twisting during cable handling
• Prevents permanent cable deformation
• Must be considered in reeling drum design
• Anti-twist element provides resistance to exceeding this limit

7.3.3 Bending Radius Requirements

According to VDE 0298 Part 3:

• Installation bending radius: Minimum 15-20 times cable outer diameter
• Operating bending radius: Should not be less than 12 times outer diameter
• Reeling drum diameter: Minimum 20-25 times cable outer diameter
• Advantage of polyurethane: Better flex-fatigue performance allows for tighter bends in some applications

7.4 Current Carrying Capacity

Current ratings determined per VDE 0298 Part 4 considering:

7.5 Safety Monitoring Recommendations

• Temperature Monitoring: Install RTDs or thermocouples on high-capacity cables
• Ground Fault Protection: Implement sensitive earth fault relays
• Overcurrent Protection: Properly coordinated circuit breakers or fuses
• Insulation Monitoring: Periodic megohm testing to detect degradation
• Tension Monitoring: Load cells on reeling systems to prevent over-tension

8. Precautions for Use

8.1 Storage and Handling Precautions

8.1.1 Pre-Installation Storage

• Temperature Range: Store at 5°C to 35°C to maintain polyurethane properties
• Humidity Control: Keep in dry environment (< 70% RH) to prevent moisture ingress
• UV Protection: While polyurethane is UV-resistant, prolonged storage should be under cover
• Reel Storage: Store reels vertically or horizontally on proper supports
• Shelf Life: Polyurethane cables have excellent shelf life (5+ years when properly stored)

8.1.2 Low-Temperature Handling

Although the cable is rated for -50°C static operation:

• Avoid installation at temperatures below -10°C if possible
• Allow cable to warm gradually if stored in cold conditions
• Polyurethane maintains better flexibility than rubber at low temperatures
• Never force bend cold cables; allow thermal conditioning first

8.1.3 Cable Handling Best Practices

• Use proper lifting equipment for heavy reels
• Avoid dropping or impacting cable ends
• Protect cable ends from moisture and contamination
• Maintain minimum bending radius during handling
• Monitor pulling tension; do not exceed 50% of maximum tensile load

8.2 Installation Precautions

8.2.1 Termination Requirements

• Use Approved Kits Only: Manufacturer-specified termination kits for polyurethane cables
• Cleanliness Critical: Maintain ultra-clean environment during termination
• Semiconductive Layer Removal: Precise removal per kit instructions
• Stress Control: Proper installation of stress cones/field control components
• Earth Continuity: Verify all three earth conductors properly terminated
• High-Voltage Testing: Perform factory and after-installation testing

8.2.2 Reeling System Design

Critical parameters for polyurethane cable installations:

8.3 Operational Precautions

8.3.1 Load Management

• Calculate actual load including starting currents and peak demands
• Apply proper derating factors for ambient temperature and installation method
• Implement overcurrent protection with proper coordination
• Monitor voltage drop, especially for long trailing lengths
• Consider power factor and harmonics in current rating calculations

8.3.2 Environmental Considerations

• Chemical Exposure: While polyurethane has excellent oil resistance, avoid prolonged exposure to strong acids or bases
• Abrasion Path: Keep trailing paths clear of sharp objects and severe obstacles
• Water/Slurry: Ensure proper sealing at terminations to prevent moisture ingress
• UV Exposure: Polyurethane has excellent UV resistance but minimize unnecessary exposure

8.3.3 Polyurethane-Specific Operating Notes

• Temperature Sensitivity: Polyurethane properties vary with temperature more than rubber
• Hot Environments: Avoid prolonged exposure to temperatures above 80°C
• Chemical Compatibility: Test compatibility with site-specific chemicals if unusual exposure expected
• Cleaning: Use mild detergents; avoid harsh solvents that may affect polyurethane

8.4 Maintenance Precautions

8.4.1 Inspection Schedule for Polyurethane Cables

8.4.2 Testing Precautions

• Insulation Resistance: Test at 5-10 kV DC; record temperature during test
• High-Voltage Testing: Use qualified personnel and equipment only
• Polyurethane Consideration: Temperature affects readings more than rubber
• Partial Discharge Testing: Consider for critical applications
• Documentation: Maintain detailed test records for trend analysis

9. Common Problems and Solutions

9.1 Mechanical Issues

Problem 1: Sheath Abrasion and Wear

Symptoms:

• Visible wear marks on outer polyurethane sheath
• Localized thinning of sheath material
• Exposure of inner sheath in severe cases

Causes:

• Excessive dragging over rough surfaces (though polyurethane resists this better than rubber)
• Sharp obstacles in trailing path
• Improper cable routing

Solutions:

• Inspect and clear trailing path regularly
• Install cable guides at critical wear points
• Rotate cable periodically to distribute wear
• Consider protective sleeving at severe wear locations
• Advantage: Polyurethane’s superior abrasion resistance (5-10× rubber) extends service life significantly

Problem 2: Cable Twisting and Spiral Formation

Symptoms:

• Cable develops permanent twist or spiral shape
• Difficult reeling and unreeling
• Uneven stress distribution

Causes:

• Improper reeling system setup (excessive fleet angle)
• Lack of level-winding mechanism
• Torsional stress exceeding ±25°/m

Solutions:

• Verify anti-twist polyester braid integrity
• Correct reeling system alignment and fleet angle
• Install or repair level-wind mechanism
• Implement swivel connections if appropriate
• For severe cases, cable replacement may be necessary

Problem 3: Cold-Weather Stiffening

Symptoms:

• Reduced flexibility in cold temperatures
• Difficulty in handling and reeling
• Increased risk of damage during cold handling

Causes:

• Operation near lower temperature limits
• Sudden temperature drops

Solutions:

• Advantage: Polyurethane maintains better low-temperature flexibility than rubber
• Rated for -50°C static (vs -40°C for rubber versions)
• Allow thermal stabilization before operation in extreme cold
• Consider heated storage for cables in Arctic conditions
• Reduce bending stress at temperatures below -25°C

9.2 Electrical Issues

Problem 4: Insulation Resistance Degradation

Symptoms:

• Decreasing insulation resistance readings over time
• Ground fault alarms or nuisance trips
• Elevated leakage current

Causes:

• Moisture ingress through damaged sheath
• Termination seal failure
• Natural insulation aging
• Contamination at terminations

Solutions:

• Perform detailed insulation resistance testing to locate degraded section
• Inspect and reseal all terminations
• Check for mechanical damage allowing moisture entry
• Dry-out cable if moisture contamination confirmed
• Polyurethane advantage: Better moisture barrier than some rubber compounds
• Replace cable section if degradation severe or widespread

Problem 5: Conductor Overheating

Symptoms:

• Elevated temperature at specific cable sections
• Thermal trips or alarms
• Softening of insulation (in extreme cases)
• Distinct odor from overheated materials

Causes:

• Cable undersized for actual load
• Poor connections increasing resistance
• Excessive cable coiled on drum reducing heat dissipation
• High ambient temperature not accounted for in rating

Solutions:

• Verify actual load vs cable rating with proper derating
• Inspect and repair all connections and terminations
• Minimize coiled cable on reeling drum
• Improve ventilation around cable runs
• Upgrade to larger conductor size if persistently overloaded
• Implement temperature monitoring systems

9.3 Environmental Issues

Problem 6: Chemical Attack on Sheath

Symptoms:

• Softening or swelling of polyurethane sheath
• Discoloration or surface changes
• Loss of physical properties

Causes:

• Exposure to incompatible chemicals (strong acids, bases, or specific solvents)
• Chemical spills in operating area

Solutions:

• Polyurethane resistance: Excellent resistance to oils, but some limitations with strong acids/bases
• Identify and eliminate source of chemical exposure
• Clean affected areas with compatible cleaning agents
• Assess damage extent; replace cable if structural integrity compromised
• Implement chemical containment measures
• For specific chemical environments, consult manufacturer for compatibility

Problem 7: Fire Damage Assessment

Post-Fire Evaluation:

• Halogen-free advantage: Minimal corrosive damage to surrounding equipment
• Reduced smoke damage improves equipment salvage rates
• Simplified cleanup with non-corrosive residues

Actions After Fire Incident:

• Complete electrical testing of all potentially affected cables
• Inspect for heat damage even if not directly exposed to flames
• Replace any cable showing signs of thermal damage
• Document incident for insurance and regulatory purposes
• Verify no corrosive residue on adjacent equipment (minimal with halogen-free)

9.4 Termination Issues

Problem 8: Termination Failures

Symptoms:

• Localized heating at termination
• Partial discharge detection
• Flashover or tracking at stress cones

Causes:

• Improper stress cone installation
• Contamination during termination
• Incorrect termination kit for polyurethane cable
• Moisture ingress at termination

Solutions:

• Critical: Use termination kits specifically approved for polyurethane-sheathed cables
• Re-terminate using clean-room conditions
• Verify proper stress cone dimensions and installation
• Perform partial discharge testing after termination
• Implement environmental sealing appropriate for site conditions

10. Comparison: Rubber vs Polyurethane Sheaths

10.1 Performance Comparison Matrix

10.2 When to Choose Polyurethane Over Rubber

10.3 Total Cost of Ownership Analysis

Example 10-year TCO comparison for a 6/10 kV, 3×95 mm² + 3×50/3E cable (500 meters):

Note: Values are illustrative examples. Actual costs vary by region, application, and operating conditions.

11. Technical Specifications

11.1 Complete Electrical Parameters

11.2 Thermal and Mechanical Characteristics

11.3 Environmental and Chemical Resistance

11.4 Available Cable Configurations

3.6/6 kV Specifications

Complete specifications for 6/10 kV, 8.7/15 kV, and 12/20 kV ratings available in product documentation. Contact technical support for detailed dimensional drawings and performance data.

11.5 Ordering Information

When ordering (N)TSCGEWÖU cables, specify:

1. Voltage rating (e.g., 6/10 kV)
2. Conductor configuration (e.g., 3×95 + 3×50/3)
3. Cable length required
4. Termination requirements (if any)
5. Special test certificates needed
6. Delivery timeline

Example Order Code: TSCGEWÖU-6/10kV-3×95+3×50/3-500m-CERT

Conclusion

The (N)TSCGEWÖU halogen-free round reeling cable represents the cutting edge of environmentally responsible mining cable technology. By combining proven DIN VDE 0250 Part 813 design principles with advanced polyurethane materials, this cable delivers:

• Superior Performance: Enhanced tensile strength (20 N/mm²), torsional resistance (±25°/m), and abrasion resistance (5-10× rubber)
• Environmental Leadership: Zero halogen emissions, reduced smoke generation, and recyclable materials
• Enhanced Safety: Non-corrosive fire residues, improved visibility during emergencies, and reduced personnel exposure to toxic gases
• Economic Value: Extended service life (20-25 years), reduced maintenance costs, and lower total cost of ownership
• Operational Excellence: Wider temperature range (-50°C to +80°C), better flexibility, and lighter weight

For mining operations prioritizing safety, sustainability, and performance, the (N)TSCGEWÖU cable is the optimal choice. While initial investment is higher than rubber alternatives, the combination of extended service life, reduced environmental impact, and enhanced safety delivers compelling value throughout the cable lifecycle.