To select a medium voltage SWA armoured cable, first confirm the system voltage, conductor material and size, installation environment, fault level, and applicable project standard. Then check that the cable construction—including insulation, metallic screens, steel wire armour, and outer sheath—fits the installation and electrical design. SWA means steel wire armour, which provides mechanical protection and can contribute to the cable’s earth-fault path when designed and connected accordingly. Because ratings and construction vary by standard and manufacturer, use a project-specific datasheet rather than choosing by voltage label alone.
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This guide is for procurement teams, electrical contractors, consultants, and project engineers comparing medium voltage (MV) cable options. At Zhongdong Cable Co., Ltd., we recommend sharing the full installation and electrical requirements before requesting a quotation, so the proposed construction can be reviewed against the intended use.
Medium voltage SWA cable is a power cable designed for MV distribution, with a layer of steel wire armour beneath its outer sheath. A typical construction may include a copper or aluminium conductor, conductor screen, XLPE insulation, insulation screen, metallic screen, bedding, steel wire armour, and an outer sheath. The exact layer arrangement depends on the voltage class, applicable standard, number of cores, and project specification.
The armour helps resist mechanical damage during handling and service, but it does not make a cable suitable for every route. It should not be treated as a substitute for correct trench design, protection, installation practices, or earthing design. The armour’s electrical role must also be defined by the project engineer, especially where fault-current requirements apply.
Confirm the cable’s rated voltage in the format required by the project, such as 6/10 kV or 12/20 kV. These are examples of MV voltage designations, not recommendations for a particular network; the correct rating depends on the system and its highest operating voltage. Specify the required standard and edition in the enquiry. IEC 60502-2 is one standard used for extruded-insulation power cables in the 6 kV to 30 kV range, but local regulations or utility requirements may call for different or additional specifications.
Conductor material is commonly copper or aluminium. Selection depends on factors such as required current capacity, cable dimensions, termination compatibility, and total installed cost. Conductor cross-section should be determined through electrical design, including load current, installation conditions, voltage drop, and short-circuit duty; do not select it from load current alone.
XLPE is a common MV insulation material. Many XLPE cable designs use a 90°C maximum continuous conductor temperature and a 250°C short-circuit conductor temperature for a specified short-circuit duration. These figures are design-dependent reference points, not guaranteed ratings for every cable. Confirm temperature limits, test requirements, and allowable short-circuit duration in the offered datasheet and governing standard.
The metallic screen’s material and cross-section should suit the specified earth-fault current and duration. Steel wire armour is generally associated with multicore cable constructions. For single-core AC cables, steel armour can experience magnetic effects and additional losses, so the cable designer may recommend a non-magnetic armour or another protection arrangement. Confirm the proposed design with the project engineer rather than assuming that SWA is appropriate for every core configuration.
The outer sheath should be selected for the route’s environmental conditions, which may include moisture, sunlight, chemicals, or other exposure. Ask the supplier to identify the sheath material and any applicable performance requirements. Also confirm whether the installation is direct-buried, installed in ducts, or routed on a tray, as installation method affects design and rating.
MV SWA cable may be considered for distribution links between substations, industrial facilities, infrastructure sites, and other fixed power installations where mechanical protection is required. Suitability depends on the actual route, electrical system, and local rules. An underground route, for example, needs evaluation of soil and thermal conditions, water exposure, burial design, and any specified external protection.
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For indoor or outdoor use, check the sheath and installation requirements rather than relying on the armour designation alone. For vertical sections, tight routes, or complex terminations, review the cable’s weight, minimum bending radius, pulling limits, and accessory compatibility with the installation team. These limits are construction-specific and should come from the manufacturer’s technical documentation.
Record nominal system voltage, highest system voltage if specified, frequency, load, earthing arrangement, and expected operating conditions. Provide short-circuit current and clearing time so the conductor and screen can be checked against fault duty. Include any required overload or emergency operating conditions in the design brief.
State the installation method, route length, number of circuits, ambient or soil conditions, and exposure to moisture, chemicals, or sunlight. Identify whether the cable will be installed in a trench, duct, tunnel, or on a support system. Include site constraints such as pulling access, bends, and termination locations.
Request details for conductor material and cross-section, core count, insulation, screen, armour, and outer sheath. State the required standard, voltage designation, conductor identification, and any fire or environmental requirements. If the design team has not finalized a construction detail, ask the supplier to list proposed alternatives and their implications.
Confirm that the cable’s outer diameter, weight, drum arrangement, and bending and pulling limits suit the route. Check that joints, terminations, glands, and earthing connections are compatible with the cable construction and system voltage. Accessory selection and installation should follow the project design and the relevant manufacturer instructions.
Compare like with like: a price is meaningful only when voltage rating, conductor, cross-section, core count, construction, standard, and sheath requirements match. Drum length, total order quantity, packaging, testing requirements, delivery location, and shipping terms can also affect the commercial offer. Ask suppliers to identify exclusions, such as accessories or special tests, so the comparison does not conceal differences in scope.
Minimum order quantities and production lead times depend on the requested specification, available materials, order volume, and production schedule. Rather than relying on a general estimate, provide the required quantity and requested delivery date for confirmation. For phased projects, ask whether the supplier can quote the required drum lengths and delivery plan for each phase.
At Zhongdong Cable Co., Ltd., we can review an enquiry against the information supplied and help clarify cable construction and quotation details. To support an accurate response, share the voltage designation, conductor requirements, route conditions, applicable standard, order quantity, and target delivery schedule. Where a requirement is not yet confirmed, mark it as open so it can be discussed rather than silently assumed.
The right medium voltage SWA armoured cable is the construction that meets the project’s electrical duty, installation conditions, and specified standards—not simply the cable with the closest voltage label. Define the system voltage and fault requirements first, then match conductor, insulation, screen, armour, and sheath to the route. Verify all ratings and installation limits against the supplier’s datasheet and project design.
For the next step, prepare a cable enquiry with your voltage designation, core count, conductor material and size, installation method, applicable standard, quantity, and delivery target. Send those details to Zhongdong Cable Co., Ltd. to discuss the required construction and request product information or a quotation.
Contact us to discuss your requirements of Medium Voltage SWA Armoured Cable. Our experienced sales team can help you identify the options that best suit your needs.