What Is Halogen Free Wire?

Halogen-free wire is a type of Electrical Cable designed to minimize the release of toxic and corrosive gases when exposed to high temperatures or flames. Unlike traditional wires that contain halogens like chlorine (Cl) and bromine (Br), halogen-free alternatives use materials such as polyolefins, thermoplastic elastomers (TPE), or cross-linked polyethylene (XLPE) to reduce environmental and health hazards. These wires comply with international standards such as IEC 60754, EN 50267, and UL 1685, ensuring low smoke emission and minimal halogen content.

Key Characteristics of Halogen-Free Wire

1. Low Smoke Emission

Halogen-free wires produce significantly less smoke compared to conventional PVC-insulated cables. According to IEC 61034, smoke density is measured in light transmittance, with halogen-free wires typically achieving >80% transmittance, whereas PVC Wires may drop below 20% under combustion.

2. Non-Toxic Gas Emission

When burned, halogen-free wires release minimal toxic gases such as hydrogen chloride (HCl) and hydrogen bromide (HBr). IEC 60754-1 specifies that HCl emission must be below 0.5% by weight, whereas PVC cables can emit up to 30% HCl.

3. Flame Retardancy

These wires exhibit excellent flame resistance, often meeting UL 94 V-0 or IEC 60332-1 standards. The limiting oxygen index (LOI) for halogen-free materials is typically >30%, ensuring self-extinguishing properties.

4. High Thermal Stability

Halogen-free insulation materials, such as XLPE, can withstand temperatures up to 90°C for continuous operation (IEC 60502-1) and short-circuit temperatures of 250°C.

5. Environmental Safety

Free from heavy metals like lead (Pb) and cadmium (Cd), halogen-free wires comply with RoHS and REACH regulations, making them eco-friendly.

Applications of Halogen-Free Wire

1. Public Transportation

Used in trains, subways, and aircraft due to low smoke and toxicity, meeting EN 45545-2 for railway applications.

2. Data Centers

Critical for server rooms and telecommunication hubs (e.g., TIA-568-C.3 compliant cables) to prevent corrosive gas damage to equipment.

3. Healthcare Facilities

Deployed in hospitals (IEC 60601-1) to ensure safe evacuation during fires.

4. Industrial Automation

Ideal for control panels and robotic systems (UL 1277) where flame resistance is paramount.

5. Renewable Energy

Solar and wind farms utilize halogen-free cables (IEC 62930) for UV and heat resistance.

Maintenance Guidelines

1. Regular Inspection

Check for abrasions, cracks, or discoloration every 6 months using a megohmmeter to ensure insulation resistance >1 GΩ (per IEEE 400).

2. Proper Storage

Store in dry conditions (<70% humidity) at 0-40°C to prevent hydrolysis of polyolefin materials.

3. Bend Radius Control

Maintain a minimum bend radius of 8x the cable diameter (IEC 60228) to avoid mechanical stress.

4. Cleaning

Use alcohol-based cleaners (isopropanol <70%) to remove contaminants without degrading insulation.

5. Termination Handling

Apply torque within manufacturer specifications (e.g., 0.5-2.5 Nm for terminal blocks) to prevent conductor damage.

6. Fire Prevention

Install in conduit systems (NEC Article 725) away from heat sources exceeding 90°C.

7. Documentation

Maintain test records per IEC 62446 for warranty validation, including partial discharge (<10 pC) and dielectric strength tests.