MZ and MZP 0.3/0.5 kV Coal Mine Electric Drill Cable

Hand-held and support-mounted electric coal drills are still widely used in Chinese-standard underground coal mines for blast holes, drainage holes and roof work, normally on 127 V circuits fed from a coal drill comprehensive protection unit. The drill cable is dragged across wet floors, pinched by props and rock and repeatedly coiled, so it needs a light, flexible rubber construction with a defined earth core and, where required, a screen that lets the protection unit detect damage. MZ and MZP are the coal mine electric drill cable designations defined in MT/T 818.8 for 0.3/0.5 kV.

MZ is the unscreened version: three Class 5 copper power cores and one earth core, or three power cores, one earth and one auxiliary control core, insulated with rubber and protected by a flame-retardant rubber sheath. MZP adds a semi-conductive rubber screen over each power core, so a crushed or cut core contacts the screen and trips the protection unit before an open spark occurs. The standard sizes are 2.5 mm2 and 4 mm2, for example MZ 3×2.5+1×2.5 or MZP 3×4+1×4+1×4 mm2; 1.5 mm2 and 6 mm2 versions can be made to order.

MZ and MZP belong to a different system from the BS 6708 Type 43 and Type 44 drill cables rated 125/72 V, and from the 600 V to 2000 V drilling mast cable used on surface blast-hole rigs. Under the 2026 renumbering of coal-industry standards, MT/T 818.8-2009 is now cited as KA/T 818.8-2009 with the same content year.

Explore the mining and tunneling cable range for related configurations.

MZ and MZP 0.3/0.5 kV Coal Mine Electric Drill Cable Construction & Layer Structure

The representative horizontal sample shows an MZP 0.3/0.5 kV 3x4+1x4+1x4 mm2 drill cable: three Class 5 copper power cores with rubber insulation and black semi-conductive rubber screens, one earth core, one auxiliary control core, a central rubber filler and a black flame-retardant rubber sheath.

MZ and MZP Type Designation Breakdown

• M: coal-mine flexible cable series under the MT 818 / KA 818 system
• Z: electric coal-drill cable (电钻电缆) rated 0.3/0.5 kV for 127 V drill circuits
• P: semi-conductive rubber screen over each power core (MZP construction; MZ is unscreened)
• 0.3/0.5 kV: rated power-core voltage U0/U (300 V to earth, 500 V phase-to-phase)
• 3+1 layout: three power cores plus one equal-section earth core (for example 3x2.5+1x2.5 or 3x4+1x4 mm²)
• 3+1+1 layout: three power cores, one earth core and one auxiliary control core (for example 3x4+1x4+1x4 mm²)

MZ and MZP 0.3/0.5 kV Coal-Mine Drill Applications & Duty Scope

Select MZ or MZP according to the drill protection scheme and whether the mine requires screened drill cable.

• Hand-held and support-mounted electric coal drills on 127 V circuits fed from coal drill comprehensive protection units.
• Drainage and gas-extraction hole drilling where the drill cable is repeatedly dragged across wet floors and around roof supports.
• Screened MZP installations where the protection unit relies on a semi-conductive core screen to trip when the cable is crushed.
• Export coal-mine projects using Chinese coal drills and protection units that call for MZ or MZP by designation.

MZ and MZP vs BS 6708 Type 43, Type 44 and MYP Selection Boundary

Select MZ or MZP for Chinese MT-system 0.3/0.5 kV (127 V circuit) electric coal drills; select BS 6708 Type 43 or Type 44 for 125/72 V British-standard drill systems.

Related selection resources

• Mining and tunneling cable engineering solutions
• Mining cable selection guide: 8 steps for mobile equipment
• Type 44 BS 6708 125/72 V Metallic Screened Drill Cable
• Type 43 BS 6708 125/72 V Non-Metallic Screened Drill Cable
• MYP and MYPT Screened Flexible Coal Mining Cable

MZ and MZP 0.3/0.5 kV Drill Cable Frequently Asked Questions

When should I specify MZP instead of MZ 0.3/0.5 kV drill cable?

Specify MZP when the 127 V coal drill comprehensive protection unit uses core-screen monitoring: MZP has a semi-conductive rubber screen over each power core so that crushing or cutting a core contacts the screen and trips the protection unit before an open spark occurs. Specify unscreened MZ where standard unscreened drill cable is called for.

Which core layouts and conductor sizes are available under MT/T 818.8-2009?

Both MZ and MZP are supplied in 3+1 (three power cores and one equal-size earth core) and 3+1+1 (three power cores, one earth core and one auxiliary control core) layouts. The standard MT/T 818.8 (now KA/T 818.8) sizes are 2.5 mm² (77/0.20 mm, 25 A) and 4 mm² (126/0.20 mm, 34 A), with 1.5 mm² and 6 mm² available made to order.

How do MZ and MZP differ from BS 6708 Type 43 and Type 44 drill cables?

MZ and MZP are Chinese MT-system 0.3/0.5 kV cables with 3+1 or 3+1+1 cores for 127 V drill circuits, whereas BS 6708 Type 43 and Type 44 are British-standard 125/72 V five-core drill cables with cradle separators and collective or metallic screens.

What are the minimum order quantity and manufacturing lead time?

The minimum order quantity (MOQ) is 50 m and the manufacturing lead time is 7 to 45 working days. Any destination-mine certificate requirement is confirmed before quotation.

MZ and MZP Dimensions, Current Rating & Technical Specifications

MZ and MZP Key Specifications

• Models covered: MZ (unscreened) and MZP (semi-conductive rubber screened) coal mine electric drill cables
• Voltage & typical circuit: 0.3/0.5 kV (300/500 V) rated voltage; designed for 127 V hand-held electric coal drill circuits
• Core layouts & sizes: 3+1 and 3+1+1 layouts; 2.5 mm² and 4 mm² standard to MT/T 818.8 (1.5 mm² and 6 mm² made to order)
• Construction: Class 5 flexible copper, rubber insulation, short-lay cabling around central rubber filler, 3.0–3.5 mm rubber sheath
• Design references: MT/T 818.8-2009 (KA/T 818.8-2009), MT 818.1-2009, MT/T 386-2011, GB/T 3956 / IEC 60228

MT/T 818.8 MZ 0.3/0.5 kV Unscreened Coal Mine Electric Drill Cable Schedule

MT/T 818.8 MZP 0.3/0.5 kV Screened Coal Mine Electric Drill Cable Schedule

Current ratings are nominal values for a single cable in air at 25 C and 65 C conductor temperature; dimensions and masses are nominal reference values confirmed on the quotation drawing.

China MA safety-mark coverage is model- and size-specific; no MA coverage is claimed for MZ or MZP on this page, so state the certificate requirement of the destination mine when requesting a quotation.

ASCII part references for BOM and ERP entry: MZ 3x1.5+1x1.5, MZ 3x1.5+1x1.5+1x1.5, MZ 3x2.5+1x2.5, MZ 3x2.5+1x2.5+1x2.5, MZ 3x4+1x4, MZ 3x4+1x4+1x4, MZ 3x6+1x6, MZ 3x6+1x6+1x6, MZP 3x1.5+1x1.5, MZP 3x1.5+1x1.5+1x1.5, MZP 3x2.5+1x2.5, MZP 3x2.5+1x2.5+1x2.5, MZP 3x4+1x4, MZP 3x4+1x4+1x4, MZP 3x6+1x6, MZP 3x6+1x6+1x6.

MZ and MZP Standards & Test References (MT/T 818.8-2009, MT/T 386-2011)

Certifications and document support

TEBAOFLEX company certificates and quality system documentation

National Public Service Platform for Standards Information (SAMR, China) — GB/T and coal-industry standard records