Garden Lighting Technical Information

Garden Lighting Designs & Landscape Lighting Designs

Transformer Transformer – Devise for changing voltage, usually from 240v to low voltage commonly 12v. The reason for this is that when  it is much safer and easier to run cables across beds and lawns than to run mains voltage. 
   
Luminaire Current term for fitting
   
Lamp Industry name for a light bulb
   
Wattage Load required to power one or a number of fittings.
   
Voltage Drop

When running distances in 12 volts the cable needs to be matched to the load and distance. Otherwise you may end up with less than 12 volts at the end of the cable run. This will not cause damage to the luminaire but if the voltage drop is large then the light produced will have a slightly yellow effect and may also seem slightly dim.
   
   
IP Ratings

The rating the product (luminaire) is given to show its resistance to particles in the atmosphere and its resistance to water. The first number is resistance to particles and the second number shows the resistance to water. IE IP 67 OR IP 68 for pond or pool lighting.  
   
  Click here to see Garden Lighting IP Ratings Chart
   

Low Voltage Cabling

This is the cable used to run out from the transformer to the product (luminaire). The size of cable depends on the total wattage of garden lights and length of cable run.  
   
  Click here to see Garden Lighting Voltage Drop Chart
   
Waterproof Connections There are many different ways of making all joints fully waterproof, this is very important when outdoor as without correct joints when the lamp cools it will pull in moisture from the ground and also the atmosphere. This will rapidly deteriorate the lamp and lamp holder and will eventually cause failure.
   
Heat Shrink Available in kit form consisting of 2 crimps and an outer heat shrink seal. Or in large rolls and cut to size. The seal shrinks when heated from the center outwards thus providing a water tight seal.
   
Resin Joint These consist of two chemicals that when mixed together for a hard impervious resin.  Very useful to fill enclosure boxes that are to be buried underground.
   
IP Enclosure These are waterproof boxes that must be fitted with the correct glands to ensure watertight seal where the cables exit the box.  Very useful to run a number of cables out to each  product (luminaire).

Garden Lighting Voltage Drop Chart

Maximum distances in metres for stated wattage with Voltage Drop of up to 1 Volt

Load in Watts

2.5 mm cable

(metres)

4 mm cable

(metres)

6 mm cable

(metres)

10 mm cable

(metres)

20 W

 

40

 

65

 

97

 

164

 

40 W

 

20

32

 

48

 

81

 

50 W

 

16

 

25

 

38

 

65

 

60 W

 

13

 

20

 

32

 

54

 

70 W

 

11

 

18

 

27

 

46

 

80 W

 

10

 

16

 

24

 

40

 

90 W

 

8.5

 

14

 

21

 

35

 

100 W

 

8

 

13

 

19

 

33

 

120 W

 

6

 

10

 

16

 

27

September 2000


Garden Lighting IP Ratings

 Fiirst Number - Protection against solids

Second Number Protection against liquids

   
     

0

No Protection

No Protection

1

Protected against solid objects over 50mm

Protected against vertically falling drops of water

2

Protected against solid objects over 12mm

Protected against direct sprays up to 15° from vertical

3

Protected against solid objects over 2.5mm

Protected against direct sprays up to 60° from vertical

4

Protected against solid objects over 1mm

Protected against direct sprays from all directions - limited ingress permitted

5

Protected against dust - limited ingress permitted

Protected against low pressure jets from all directions - limited ingress permitted

6

Totally protected against dust

Protected against strong jets from all directions - limited ingress permitted

7

 

Protected against effects of immersion from 15cm - 1m

8

 

Protected against long periods of immersion under pressure


Garden Lighting Technical Notes:

IP numbers are often quoted on enclosures, connectors and fittings etc. to indicate protection from solids, liquids and impact. The table above gives a description of these ratings.

Installation & Wiring Diagram.

Click on image to download a PDF wiring diagram

Wiring Diagram PDF