Garden Lighting Help sheet  No. 8: - Installation materials

Low voltage cables

Our low voltage garden lighting cable is a double insulated rubber type with a tough outer sheath impervious to moisture and salts in the soil to suit most garden lighting applications. The cable is usually run under bark or gravel mulch to aid flexibility in locating garden lights, but we recommend the cable for use under decking and over pergolas to resist condensation as well as rain. Protective conduit may be used where cable might be vulnerable, for example where it crosses under a grass path where lawn edging during maintenance might damage the cable.  Black clips are available for neat clipping of cable over pergolas to downlights and under decking to L.E.D. deck lights. 

2.5mm² ground burial low voltage cable is used for most spike mount garden spotlights, recessed uplights and other ground mounted exterior halogen light fittings. Wire 50w and 75w garden light fittings direct from the transformer position to reduce cable voltage drop to a minimum – see Help Sheet 3 - Low voltage cabling layout for further guidance. Overall diameter 10mm.  8m per garden light is a useful rule of thumb when working out quantity required.

1.5mm² ground burial low voltage cable is most commonly used for low power applications such as led (L.E.D. - light emitting diode) deck lights and direct cabling to one or two 20w halogen garden lights over short distances. 

T9962 - Cable joint kit - use this kit to connect a low voltage garden light to the end of a cable from the transformer

Kit comprises blue crimped connectors and medium wall adhesive-lined rubber tubing which is heat-shrunk over the joint to make it completely weatherproof; requires a crimp tool and a heat source such as an electric heat gun or low-heat blowlamp. Cable joint kit is required for most low voltage garden lights, spike-mount exterior spotlights and outdoor recessed lights (other than wall or surface mount outdoor spotlights which have a connection space inside the base plate) where the cable fitted isn’t connected directly to a transformer. Heat shrink ratio 3:1. Suitable for connecting to the end of 1.5mm² or 2.5mm² ground burial low voltage cable with overall diameter up to 10mm

T9963 - Cable splice kit - use this kit to splice the lead from a 12v garden light into a run of cable to other garden lights.

Kit comprises yellow crimped connectors and medium wall adhesive-lined rubber tubing which is heat-shrunk over a “Y” joint; silicon injection prior to heat shrinking is recommended to make it completely weatherproof; requires a crimp tool and a heat source such as an electric heat gun or low-heat blowlamp. Cable slice kit is required for most low power garden lights such as led (l.e.d. - light emitting diode) deck lights and 20w halogen garden lights where low power permits longer cable runs and splicing of the cable on the fitting into a cable running to one or more additional fittings. Heat shrink ratio 3:1. Suitable for splicing into 1.5mm² or 2.5mm² ground burial low voltage cables.

T9969 - Underground joint kit - Use this kit to connect flexible rubber cables (3 core HO7-RNF is recommended) from 240v garden lights to a steel wire armoured supply cable below ground, avoiding use of visible junction boxes.

Kit comprises a 100 x 100 x 60mm polycarbonate enclosure to be drilled for the number and type of cable glands needed and a two-part resin sealant pack. Cables are connected in the enclosure and operationally tested; the sealant pack is then mixed in its own sealed pouch & poured into the enclosure to completely seal it. The resin sets in about 30 minutes, after which the enclosure can be buried, with a paving slab and warning tape over it if it contains 240 volt connections. May be used to connect mains voltage lights to armoured cables avoiding the use of surface junction boxes, to make up a cable hub for distribution of low voltage cabling to several light fittings or to act as a through-joint for supply to an in-ground transformer kit. Order glands separately. Ideal for bollard light installations.

T9972 low voltage cable gland

For terminating 12v garden lighting cables into a weatherproof enclosure. Black IP68 20mm gland, for cables up to 10mm diameter, provides strong cable retention as well as waterproofing the cable entry.

Weatherproof Enclosures and Junction Boxes