LAPP ÖLFLEX® HEAT 180 GLS 3G4 (0046226): The Steel-Armoured Silicone Cable That Handles Heat and Hard Knocks

Ordinary PVC cable has a simple weakness: heat. Run it near a furnace, kiln or heating element and the insulation hardens, cracks and eventually fails. Silicone-insulated cable solves the heat problem, but silicone is soft and easily damaged in busy industrial areas. The ÖLFLEX® HEAT 180 GLS 3G4 was designed to answer both problems at once, and this guide explains what it is, what it can and cannot do, and where it belongs.

What Is the ÖLFLEX® HEAT 180 GLS 3G4?

The ÖLFLEX® HEAT 180 GLS 3G4 (Article 0046226) is a high-temperature silicone power and control cable from LAPP. It has three fine-stranded copper cores of 4 mm², including a green-yellow protective earth conductor, and is rated to operate from -50°C to +180°C. In LAPP's catalogue, the GLS range is described as steel-armoured silicone cable for increased mechanical stress, so the heat resistance of silicone is combined with a close-meshed braid of galvanised steel wires that protects against mechanical damage.

Key Specifications

• Cores: 3G4 (three cores of 4 mm², including earth)
• Conductor: Fine-stranded tinned copper, Class 5 per IEC 60228 / VDE 0295
• Insulation: Silicone rubber, colour-coded cores with green-yellow earth
• Protection layer: Close-meshed galvanised steel wire braid for mechanical protection
• Rated voltage: 300/500 V
• Temperature range: -50°C to +180°C
• Outer diameter: approximately 12.9 mm
• Weight: approximately 300 kg/km
• Flame behaviour: Flame-retardant per IEC 60332-1-2
• Halogen-free per IEC 60754-1, with no corrosive gases on burning per IEC 60754-2
• Cold-resistant and CE marked
• Minimum bending radius: 4 x outer diameter for fixed installation, 20 x outer diameter for occasional flexing

Why the Steel Braid Matters

Silicone insulation resists heat extremely well, but it is soft. In steel works, foundries and heavy plant, cables can be knocked, rubbed or crushed by moving equipment. The galvanised steel braid in the GLS design shields the cable against that kind of mechanical stress. LAPP states that this gives longer durability in harsh applications than conventional silicone cables.

There is a second safety benefit worth knowing. When silicone burns, it leaves behind silicon dioxide ash on the conductor, and this ash keeps insulating properties after combustion. That can help maintain circuit integrity in a fire situation, which is one reason silicone cables are favoured near furnaces.

Where This Cable Gets Used

LAPP lists typical applications for ÖLFLEX® HEAT 180 GLS in areas with high ambient temperatures and occasional mechanical stress:

• Steel and glass works
• Cement and ceramic works
• Foundries
• Shipbuilding
• Furnace construction
• Heating systems, ovens and industrial machinery operating in hot zones

Important Installation Limits

This is a specialist cable, and its limits matter as much as its strengths. LAPP's own product information makes two points clear:

• Dry conditions only. The cable is suitable only for use in dry conditions, so it should not be installed where it will sit in water or constant moisture.
• Ventilation is required. The mechanical properties of silicone cables decrease from around +100°C when air is absent, so the cable should not be buried in sealed, unventilated spaces at high temperature.

Also remember that current-carrying capacity falls as ambient temperature rises. A 4 mm² cable can carry less current at +150°C than at room temperature, so check derating guidance from LAPP when sizing the cable for hot zones, rather than relying on the conductor size alone.

3G4 vs the Smaller 3G1: Which Size?

LAPP's HEAT 180 GLS range includes smaller sizes such as 3G1 for light-duty control and signal wiring. The 3G4 is the heavier option, with a 4 mm² conductor suited to power connections such as heater feeds, motor leads near hot equipment, and other circuits that draw more current. Choose the size from the actual load current, apply temperature derating, and confirm the cable's outer diameter will fit your glands and routing.

For the smaller 3G1 version and how HEAT 180 compares with CLASSIC 110 and CONTROL 110 cables, see our ÖLFLEX® control cable comparison guide. For glands to terminate this cable, see our SKINTOP® cable gland guide.

Tips Before You Order

• Confirm the real temperature at the cable's location, not just the ambient room temperature. Radiant heat from furnaces can be much higher.
• Check ventilation and dry-location suitability against the installation conditions.
• Choose the right glands. Armoured, high-temperature cable needs suitable gland and termination methods. Confirm the correct gland type with your supplier.
• Allow for bending radius. Occasional flexing needs a radius of at least 20 times the outer diameter, which is large for a 12.9 mm cable.
• Use a genuine product. At high temperature, a counterfeit or lower-grade cable can fail early and unsafely.

Why Buy Genuine LAPP Cables from SB Smart

SB Smart supplies genuine LAPP ÖLFLEX®, UNITRONIC® and SKINTOP® products, including the HEAT 180 GLS range, with GST invoicing, competitive B2B pricing, and PAN India delivery. Their technical team can help confirm cable size and suitability for your heat and mechanical conditions before you order.

Frequently Asked Questions (FAQ)

1. What is the ÖLFLEX® HEAT 180 GLS 3G4 used for? It is a high-temperature silicone power and control cable with a steel-wire braid for mechanical protection, used in steel and glass works, cement and ceramic plants, foundries, shipbuilding and furnace construction.

2. What temperature range does it handle? It is rated for -50°C to +180°C.

3. What does "3G4" mean? It means three cores, including a green-yellow earth conductor, each with a 4 mm² cross-section.

4. What is the voltage rating? It is rated for 300/500 V.

5. Is this cable flame-retardant and halogen-free? Yes. It is flame-retardant per IEC 60332-1-2 and halogen-free per IEC 60754-1, with no corrosive gases released on burning.

6. Can I use it outdoors or in wet locations? LAPP states it is only suitable for use in dry conditions. Do not install it where it will be exposed to water or constant moisture.

7. Why is ventilation important for silicone cable? LAPP notes that the mechanical properties of silicone cables decrease from +100°C when air is absent, so adequate ventilation is needed at high temperatures.

8. Where can I buy genuine LAPP ÖLFLEX® HEAT 180 GLS 3G4 in India? SB Smart supplies the genuine LAPP ÖLFLEX® HEAT 180 GLS 3G4 with GST invoicing, technical support, and PAN India delivery.

Final Thought

Heat-resistant cable is only half the job when the environment is also rough. The ÖLFLEX® HEAT 180 GLS 3G4 pairs silicone insulation rated to +180°C with a steel braid that shrugs off mechanical abuse, giving steel plants, foundries and furnace installations a cable built for both. Respect its dry-location and ventilation limits, size it with temperature derating in mind, and it will do its job reliably in places where ordinary cable would not last.