Questions about Transformers

Q. What is a transformer and why do I need one?

A. A transformer is an electrical device which changes voltage from one level to another. In garden lighting this is usually from 240 volts (standard house mains) to 12 volts. Transformers are located near a 240v power source in the garden or near or in a building. Flexible low voltage cable runs from the transformer to the lights , The low voltage cable typically runs under mulch and in places where 240v cable can not run due to the danger of electrocution. 12volt system will no harm anyone who comes in contact with the current

Q. Can the transformer be mounted outside?

A. Yes. DIY Garden Lights have a range of exterior garden lighting transformers that are housed in black or green weatherproof IP rated boxes, These are to be mounted on a wall or post where they are hidden behind planting Also an in-ground range of transformers are available for locations where it would better to hid the transformer completely

Q. How many lights can I power from one transformer?

A. DIY Garden Lights have a wide range of transformers which suit all applications. The transformer come in a number of wattage ratings, between 50 and 600W. The amount of power a light needs is dependent on the size of the lamp installed, for example a 20W halogen lamp requires 20W of power. As a rule of thumb we recommend that the total amount of power required by the light fittings not exceed 80% of the transformers capacity.

Therefore a 100W transformer could power 4x20W lamps, or any combination that equals 80W ie. 1x50W up light and 3x 10W path lights. The extra capacity is to allow for voltage drop if the cable runs are slightly outside the recommended limits or the lamp sizes need to be increases as the plants grow or perhaps the addition of an extra light at a later time.

Make sure the transformer is at least 60% loaded. ie. don't wire one low power light to a big transformer in the expectation of installing lots of other lights later - all you will do is over-volt the small lamp and shorten the bulbs life !