armoured vs non-armoured mining cable

BS 6708 Type 21 Trailing Cable

What is BS 6708 Type 21 Trailing Cable?

BS 6708 Type 21 mining cable represents an advanced variant of galvanized steel pliable wire armoured flexible cables specifically engineered for demanding mining and quarrying applications requiring a dedicated fourth earth conductor. This four-core configuration distinguishes Type 21 from the three-core Type 20, providing enhanced safety features and compliance with electrical regulations that mandate separate protective earth conductors in mining installations. Key Identification: Type 21 cables feature four unscreened cores (three phase conductors plus one earth conductor) laid up around an elastomeric cradle without contacting each other, protected by galvanized steel pliable armour between inner and outer sheaths. Rated at 640/1100V with a 3kV test voltage, these cables are designed for use in deep mines where explosive gases and dust can accumulate, as well as surface operations supplying excavating, crushing machines and equipment.
Type 20 BS 6708 Mining Cable

What is Type 20 BS 6708 Mining Cable?

BS 6708 Type 20 mining cable represents a specialized category of galvanized steel pliable wire armoured flexible cables engineered for the most demanding mining and quarrying applications. This cable type is characterized by its robust construction featuring three unscreened cores laid up around an elastomeric cradle without contacting each other, protected by galvanized steel pliable armour that provides exceptional mechanical protection while maintaining the flexibility essential for mobile mining equipment applications. Key Identification: Type 20 mining cables are classified within BS 6708 as cables with galvanized steel pliable wire armouring, featuring unscreened cores and a rated voltage of 640/1100V. These cables are specifically designated for use in deep mines where explosive gases and dust can accumulate, as well as surface operations for supplying excavating, crushing machines, and equipment requiring robust mechanical protection.
Type 7 Mining Cable to BS 6708

What is Type 7 Mining Cable to BS 6708?

Type 7 mining cables represent a critical category of flexible trailing cables designed specifically for the demanding conditions encountered in underground coal mining operations. These cables conform to the rigorous requirements established by British Standard BS 6708, which has become an internationally recognized benchmark for mining cable safety and performance. The standard was developed through decades of mining industry experience and addresses the unique electrical and mechanical challenges present in potentially explosive underground environments. According to BSI Knowledge, BS 6708 specifications establish comprehensive requirements for flexible cables used at mines and quarries, ensuring that these critical power transmission components meet stringent safety and performance criteria. The Type 7 designation specifically identifies non-armoured cables with individually metallic screened cores rated at 640/1100V, engineered for both fixed installation and flexible operation in coal face cutting equipment.