PVC flexible cable — flex — is multicore cable for appliance tails, machine connections, trailing leads and anything that has to be moved, coiled or handled. This range is RR Kabel flex in 2, 3, 4 and 5-core, with conductor sizes from 0.75mm² upwards.
How many cores do I need?
2-core carries live and neutral only, for double-insulated equipment that needs no earth. 3-core adds an earth and is the usual choice for single-phase appliances and portable equipment. 4-core covers three phases and earth, for motors and three-phase machines with no neutral. 5-core is three phases, neutral and earth — the standard for three-phase equipment and submains where a neutral is required.
Flex or fixed wiring cable?
Flex is stranded so it tolerates bending and vibration, which is exactly what building wire is not built for. The trade-off runs the other way too: flex is not a replacement for fixed wiring cable buried in a wall or pulled into conduit, and it should not be used to extend a permanent circuit. Keep it for the connection between a fixed outlet and the equipment.
What size for the appliance?
Work from the equipment's current draw, then allow for the length of the lead, how it is run and how warm the space gets — a lead coiled behind a machine or run through a hot plant room carries less than the same cable in open air. Check the rating plate on the equipment, and have an electrician confirm the size for anything hard-wired or three-phase.
