MYP-0.66/1.14kV
MY / MYP Rubber-Sheathed Flexible Trailing Cable for Coal Shearers
Built to be dragged over rock: fine-strand conductor, EPR insulation and a tear-resistant rubber sheath.
A trailing cable spends its life being pulled along the face behind a shearer or roadheader, over broken rock, through water and under the weight of passing machinery. Conductivity is seldom the constraint at these sizes; what ends service is sheath tear, crushed cores at a bend, or strand fatigue where the cable enters a gland or a reel. MY answers that with a Class 5 fine-strand conductor, EPR insulation that tolerates heat and repeated flexing, and a heavy chlorinated-polyethylene or polychloroprene sheath chosen for tear and abrasion resistance.
MYP adds screening. Each power core carries a semiconductive layer and a tinned copper braid, which is what 1.14 kV duty demands in a gassy atmosphere, because a phase-to-earth fault has to be detected and cleared before it arcs. Voltcore builds MY at 0.38/0.66 kV and MYP at 0.66/1.14 kV in 3+1 and 3+2 arrangements, with pilot and earth cores laid into the same assembly so one cable carries power, earth monitoring and control.
Specification
| Item | Value |
|---|---|
| Rated voltage U0/U | MY 0.38/0.66 kV; MYP 0.66/1.14 kV |
| Conductor | Fine-strand copper, Class 5, plain or tinned, IEC 60228 |
| Separator | Polyester tape over the conductor to stop insulation penetration |
| Insulation | EPR ethylene-propylene rubber, 85 °C conductor rating |
| Screening (MYP) | Semiconductive layer plus tinned copper braid per power core, coverage 80% minimum |
| Core arrangement | 3+1 and 3+2, with pilot and control cores on request |
| Sheath | Heavy-duty CPE or PCP rubber, oil, tear and abrasion resistant |
| Flame and antistatic | MT 386 flame propagation and surface resistance |
| Min bending radius | 6 × OD free; 10 × OD over sheaves and reels |
| Cross-section range | 4 – 150 mm² power cores; pilot cores 2.5 – 6 mm² |
| Pulling tension | Taken on a strain-relief grip; maximum tension stated per size on request |
Layer-by-layer construction
Listed from the conductor outward. Read this alongside the specification table — the two together tell you whether the cable will survive its installation method.
- 1. ConductorClass 5 fine-strand copper, plain or tinned, IEC 60228
- 2. SeparatorPolyester tape over the conductor to prevent insulation penetration into the strand
- 3. InsulationEPR ethylene-propylene rubber, colour-coded, 85 °C conductor rating
- 4. Core screen (MYP)Semiconductive layer plus tinned copper wire braid at 80% minimum coverage per power core
- 5. Lay-upPower cores, earth core and pilot cores laid together with rubber filler
- 6. Outer sheathHeavy-duty CPE or PCP rubber, tear and abrasion resistant, MT 386 flame tested
Reference dimensions and weights
| Nominal cross-section (mm²) | Conductor structure (n × mm) | Insulation thickness (mm) | Sheath thickness (mm) | Approx. overall diameter (mm) | Approx. weight (kg/km) | Max. DC resistance at 20 °C (Ω/km) |
|---|---|---|---|---|---|---|
| 3 × 16 + 1 × 10 | 126 / 0.40 | 1.6 | 3.4 | 34.8 | 1980 | 1.21 |
| 3 × 25 + 1 × 16 | 196 / 0.40 | 1.8 | 3.6 | 40.2 | 2820 | 0.780 |
| 3 × 35 + 1 × 16 | 276 / 0.40 | 1.8 | 3.8 | 43.6 | 3480 | 0.554 |
| 3 × 50 + 1 × 16 | 396 / 0.40 | 2.0 | 4.0 | 48.4 | 4480 | 0.386 |
| 3 × 70 + 1 × 25 | 360 / 0.50 | 2.0 | 4.2 | 54.0 | 5900 | 0.272 |
| 3 × 95 + 1 × 35 | 475 / 0.50 | 2.2 | 4.4 | 60.2 | 7600 | 0.206 |
| 3 × 120 + 1 × 35 | 608 / 0.50 | 2.4 | 4.6 | 65.8 | 9300 | 0.161 |
| 3 × 150 + 1 × 50 | 760 / 0.50 | 2.4 | 4.8 | 71.4 | 11400 | 0.129 |
Reference figures for preliminary sizing and drum planning. Overall diameter and weight vary with strand construction and sheath thickness tolerance; certified drawings are issued with each quotation.
Engineering characteristics
- Class 5 fine-strand conductor with 6 × OD bending radius keeps the cable workable where it is dragged round the face and wound onto a reel.
- EPR insulation rated 85 °C tolerates heat build-up inside a wound reel and stays flexible after repeated flexing.
- MYP screening — semiconductive layer plus tinned copper braid at 80% coverage on each power core — lets earth-fault protection clear a fault before it arcs at 1.14 kV.
- Heavy-duty CPE or PCP sheath selected for tear strength and abrasion against rock, tested to MT 386 for flame and antistatic behaviour.
- Pilot and earth cores laid into the same assembly, so power, earth monitoring and control run in one cable rather than two.
- Maximum pulling tension stated per size, with load taken on a strain-relief grip rather than on the conductors.
- Sheath resists mine water, hydraulic oil and cutting emulsion, the fluids that normally make a rubber sheath swell and crack.
Typical applications
- Power supply to longwall shearers and ploughs
- Roadheader, continuous miner and roof bolter trailing supplies
- Face conveyor, stage loader and crusher drives
- Mobile pumps, fans and compressors moved along the face
- Shuttle car and man-riding vehicle supplies
- Temporary and advancing face distribution panels
Ordering options
- MYP at 0.66/1.14 kV with per-core screening, or MY unscreened at 0.38/0.66 kV
- Additional pilot and control cores in 2.5, 4 or 6 mm²
- Tinned copper conductor and braid for wet and acidic mine water
- Extra-heavy or oil-resistant sheath grade for faces with high hydraulic-fluid exposure
- Drum lengths cut to the face advance, with ends capped and tagged
Standards manufactured to
- MT 818
- MT 386
- GB/T 12972
- IEC 60228
Manufactured to other standards on request. Send the standard number with your RFQ and we will quote against it rather than against a near-equivalent.
Price and availability for MY / MYP Flexible Mining Trailing Cable
Include cross-section, core count, voltage grade, route length and installation method — those five determine price more than anything else on the page.
- Engineer-reviewed before pricing
- Reference drawings issued with the quotation
- Free sample up to free sample up to 5 m
MY / MYP Flexible Mining Trailing Cable — frequently asked questions
What is the difference between MY and MYP cable?
MYP adds a semiconductive layer and a tinned copper braid to each power core. That screening is required at 0.66/1.14 kV in a gassy atmosphere, because it gives earth-fault current a defined metallic path so protection trips before an arc forms. MY is unscreened and used at 0.38/0.66 kV on smaller machines where the lower voltage does not require it.
What actually limits the service life of a trailing cable?
Mechanical damage, not electrical ageing. Keep the bending radius at 6 × OD free and 10 × OD over sheaves and reels, pull only on a strain-relief grip, and keep the cable off sharp rock edges. Inspect the sheath at every shift: a tear that reaches the core screen is a cut-out, while a shallow score can be repaired with the approved cold-cure compound.
Can a damaged trailing cable be repaired underground?
Shallow sheath damage can be repaired with the cold-cure rubber kit Voltcore supplies, where the mine's procedure allows it. Damage reaching the insulation, the screen or the conductor means cutting out that section and fitting a coupler. Some mines prohibit splices in trailing cable entirely, so confirm the site rule before ordering repair compound.
Should I specify tinned or plain copper conductor?
Tinned for wet, acidic or saline mine water and where terminations sit in water, because tin slows corrosion of the fine strands and keeps the crimp stable. It costs more and adds a small amount of resistance. Plain copper is standard for dry sections and is the default when the specification does not say otherwise.