Medium Voltage cables are specialized cables designed for carrying voltages ranging between 3.3kV and 66kV. With either aluminum or copper conductors, they can be constructed in either circular or Milliken configurations, depending on the size. Insulation is typically XLPE, however, EPR is used when extra flexibility is required. MV cables feature a copper wire screen up to 25kA, to carry fault current and ensure the circuit breaker blows quickly to prevent injury if the cable is damaged.
There are a range of options available when specifying the construction of a medium voltage cable. Cables to be installed in northern areas of Australia often feature nylon jacketing to provide durable termite resistance, whilst MV cables in tropical areas often have water blocking and moisture barriers.
When mechanical protection is required, single core MV cables utilize an aluminium wire armour (AWA), and 3 core MV cables utilize a galvanized steel wire armour (SWA). The sheath on a MV cable can be comprised of PVC, HDPE or a low smoke zero halogen (LSZH) compound.
| Conductor Materials | Up to 2000mm2 diameter. | Copper
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Aluminium
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| Conductor Shapes |
Circular
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Miliken
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| Cable Screening | Copper Wire Screens
Up to 25kA |
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| Sheathing Materials | PVC – (5V-90)- rated at 90°C.
HDPE – (High density polyethylene) – rated at 90°C. Greater durability & moisture resistance.
LSZH – Low Smoke Zero Halogen – Fire retardant with non-toxic emissions. |
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| Termite Resistance | Nylon Jacketing |  |
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| Moisture Barrier | Water Blocking Tape- Linear Moisture Resistance.
APL – Aluminium Poly laminate – Radial moisture resistance. |
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| Armouring | AWA – Aluminium Wire Armour – used on single core cable.
SWA – Steel Wire Armour – used on multicore cable. |
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