Application & Operating Conditions
BS 6708 Type 62, Type 63, and Type 64 are 640/1100 V individually screened, pliable wire armoured (PWA) flexible cables used for high-integrity underground coalface lighting networks, single- and three-phase auxiliary pumps, and crushing/excavating control-power feeders in gassy deep mines and surface quarries.
640/1100 V Screened Lighting & Auxiliary Power
Upgrades standard 320/550 V unscreened Type 70/71 lighting feeders to full 640/1100 V insulation with individual metallic/nylon screens on every 4 mm² core.
2-, 3-, and 4-Core Modular Selection
Type 62 (2×4 mm²) serves single-phase lighting/signalling trunks; Type 63 (3×4 mm²) serves 3-phase power; Type 64 (4×4 mm²) adds a fourth screened pilot or neutral core.
Parallel Screen + Steel Armour Fault Path
Inter-contacting copper/nylon core screens (2.8–5.5 Ω/km in parallel) work alongside the galvanized pliable steel armour (4.16–4.91 Ω/km) for ultra-fast earth-leakage tripping.
Type 62/63/64 vs Type 70/71 Distinction: Unlike BS 6708 Type 70 & Type 71 (320/550 V, unscreened cores), Types 62, 63, and 64 are rated at 640/1100 V and incorporate individual composite copper/nylon braided screens (6.00 mm screen diameter) over every 4 mm² core.
Cable Construction (BS 6708 Types 62, 63 & 64)
Each 4 mm² Class 5 tinned copper core is EPR-insulated and individually composite-screened before being cushioned in rubber bedding and armoured with galvanized steel pliable wire strands.
| Layer / Component | Material & BS 6708 Engineering Specification |
|---|---|
| 1. Conductors | Electrolytic flexible stranded tinned copper wire, IEC 60228 Class 5 (56/0.30 mm stranding, 2.60 mm diameter, 4 mm² nominal cross-section). |
| 2. Core Insulation | Ethylene Propylene Rubber (EPR) insulation extruded to 4.80 mm nominal core diameter (minimum insulation resistance 590 MΩ·km). |
| 3. Individual Core Screens | Composite tinned copper wire and nylon braided screen over every phase and pilot core (6.00 mm nominal diameter over screen). |
| 4. Core Lay-Up | Two (Type 62), three (Type 63), or four (Type 64) composite individually screened cores laid up in contact with each other. |
| 5. Inner Bedding & Pliable Armour | Extruded rubber-based inner bedding compound (16.2–20.7 mm diameter) armoured with galvanized steel pliable wire strands between inner and outer sheaths. |
| 6. Outer Sheath | Heavy-duty black chloroprene (PCP) outer sheath, flame-retardant, oil-resistant, and abrasion-resistant. |
BS 6708 Type 62 / 63 / 64 Cross-Section (Type 64 Shown): Individually composite-screened 4 mm² EPR cores laid in contact inside rubber inner bedding, galvanized steel pliable wire armour, and a black PCP outer sheath.
Technical Characteristics
Complete dimensional, reactance, insulation resistance, and voltage-drop specifications in accordance with BS 6708 Types 62, 63, and 64.
| Parameter | BS 6708 Rated Value |
|---|---|
| Reference Standard | BS 6708 (Types 62, 63 & 64 Screened Pliable Wire Armoured Cables) |
| Rated Voltage (Uo/U) | 640 / 1100 V AC |
| Routine AC Test Voltage | 2.5 kV AC |
| Core Configurations | Type 62: 2×4 mm² | Type 63: 3×4 mm² | Type 64: 4×4 mm² |
| Continuous Current Rating | 28 A across all three types |
| Nominal Reactance (50 Hz / 60 Hz) | 0.119 Ω/km (50 Hz) / 0.143 Ω/km (60 Hz) |
| Minimum Insulation Resistance | 590 MΩ·km |
| Voltage Drop | 12.38 mV/A/m (Type 62 Single-Phase) | 10.72 mV/A/m (Types 63 & 64 Three-Phase) |
BS 6708 Type 62, Type 63 & Type 64 Complete Specification Tables
Nominal core/screen dimensions, overall cable diameters, pulling tensions, weights, resistances, reactances, and voltage drops.
1. Core, Screen, Inner Sheath & Overall Cable Dimensions (Types 62, 63 & 64)
| BS 6708 Type | Nominal Size (mm²) | Stranding (No./mm) | Cond. Dia. (mm) | Insul. Dia. (mm) | Screen Dia. (mm) | Inner Sheath Dia. (mm) | Min. OD (mm) | Max. OD (mm) | Min. Bend Radius (mm) | Max. Pull (kgf) | Approx. Weight (kg/km) | Copper Weight (kg/km) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Type 62 | 2×4 | 56/0.30 | 2.60 | 4.80 | 6.00 | 16.2 – 18.2 | 23.9 | 26.4 | 270 | 48 | 1080 | 132 |
| Type 63 | 3×4 | 56/0.30 | 2.60 | 4.80 | 6.00 | 17.1 – 19.1 | 24.8 | 27.3 | 280 | 72 | 1230 | 200 |
| Type 64 | 4×4 | 56/0.30 | 2.60 | 4.80 | 6.00 | 18.7 – 20.7 | 26.4 | 29.9 | 290 | 96 | 1400 | 264 |
2. Electrical Ratings, DC Resistance, Reactance & Voltage Drop
| BS 6708 Type | Nominal Size (mm²) | Current Rating (A) | Phase Cond. DC Res. (Ω/km) | Screens in Parallel (Ω/km) | Armour DC Res. (Ω/km) | Reactance 50 Hz (Ω/km) | Reactance 60 Hz (Ω/km) | Min. Insul. Res. (MΩ·km) | Voltage Drop (mV/A/m) |
|---|---|---|---|---|---|---|---|---|---|
| Type 62 | 2×4 | 28 | 5.09 | 5.5 | 4.91 | 0.119 | 0.143 | 590 | 12.38 |
| Type 63 | 3×4 | 28 | 5.09 | 3.9 | 4.63 | 0.119 | 0.143 | 590 | 10.72 |
| Type 64 | 4×4 | 28 | 5.09 | 2.8 | 4.16 | 0.119 | 0.143 | 590 | 10.72 |
Selection Guide: BS 6708 Pliable Wire Armoured Mining Cables
Compare BS 6708 Types 62/63/64 against Type 20/21 unscreened feeders, Type 201/211 heavy roadway cables, and 320/550 V Type 70/71 lighting cables.
| BS 6708 Model | Core & Pilot Architecture, Earth Design & Primary Duty |
|---|---|
| BS 6708 Type 20 & Type 21 (640/1100V Unscreened PWA) | BS 6708 Type 20 & Type 21 (640/1100V Unscreened PWA): 3-core (Type 20) and 4-core (Type 21) unscreened EPR power cables (2.5–150 mm², 24 sizes) with 7/0.45–7/1.25 mm galvanized steel pliable wire armour. |
| BS 6708 Type 62, 63 & 64 (640/1100V Screened 4 mm² PWA) (This Product) | 2×4, 3×4, and 4×4 mm² individually composite-screened pliable wire armoured cables for 640/1100 V coalface lighting and auxiliary equipment. |
| BS 6708 Type 201 & Type 211 (640/1100V Yellow-Stripe Roadway) | BS 6708 Type 201 & Type 211 (640/1100V Yellow-Stripe Roadway): BS 6708:1998 3-core (Type 201) and 3+Earth (Type 211) copper/nylon screened MEPR roadway & quarry trailing cables (10–120 mm²) with yellow-striped black PCP jacket. |
| BS 6708 Type 321 & Type 331 (1.9/3.3kV Blue-Stripe Roadway) | BS 6708 Type 321 & Type 331 (1.9/3.3kV Blue-Stripe Roadway): BS 6708:1998 1900/3300 V medium-voltage pliable wire armoured roadway & quarry trailing cables (25–150 mm²; screened Type 331 / unscreened Type 321) with blue-striped black PCP sheath. |
| BS 6708 Type 621 (3.8/6.6kV Heavy MV Armoured) | BS 6708 Type 621 (3.8/6.6kV Heavy MV Armoured): 3800/6600 V medium-voltage 4-core (3 phases + 1 pilot, 4×35–4×150 mm²) unscreened 5.0 mm EPR pliable wire armoured power cable tested at 15 kV AC. |
| BS 6708 Type 70 & Type 71 (320/550V Lighting PWA) | BS 6708 Type 70 & Type 71 (320/550V Lighting PWA): 4×4 and 5×4 mm² 320/550 V unscreened pliable wire armoured cables for low-voltage coalface lighting strings. |
Frequently Asked Questions (FAQ)
Key engineering questions regarding BS 6708 Type 62, Type 63, and Type 64 roadway lighting and auxiliary power cables.
How do BS 6708 Type 62, Type 63, and Type 64 map to circuit types?
The second digit indicates the number of individually screened 4 mm² cores: Type 62 contains 2 cores (single-phase lighting or signalling), Type 63 contains 3 cores (balanced 3-phase power or delta lighting), and Type 64 contains 4 cores (3-phase plus screened pilot or neutral).
Why does parallel screen resistance drop from 5.5 Ω/km on Type 62 to 2.8 Ω/km on Type 64?
All individual copper/nylon braided core screens are laid up in continuous electrical contact inside the rubber bedding. Increasing from two contacting screens (Type 62) to three (Type 63: 3.9 Ω/km) and four (Type 64: 2.8 Ω/km) places additional metallic braids in parallel, lowering overall earth-screen resistance.
What is the maximum pulling tension permitted during roadway installation?
Do not exceed 48 kgf for Type 62 (2×4 mm²), 72 kgf for Type 63 (3×4 mm²), or 96 kgf for Type 64 (4×4 mm²), and maintain minimum bending radii of 270 mm, 280 mm, and 290 mm respectively.
Need BS 6708 Type 62, Type 63 or Type 64 Cable?
Specify Type 62 (2×4), Type 63 (3×4), or Type 64 (4×4 mm²) and required drum lengths for direct TEBAOFLEX factory pricing and 2.5 kV test certification.
Explore All Mining & Tunneling Cables
