Dimmer Switch Price

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on a slight tangent, I`ve been told that if I replace normal bulbs with dimmable LEDs, I will need a special type of dimmer switch? Is this necessary?
You are correct that not all dimmer switches work with all types of light. If you are considering dimming any low energy type lights such as LED's I would suggest checking with the lamp manufacturer if there are any special dimmer requirements, as it could turn out an expensive fix if any lamps or dimmers get damaged. e.g. from an Osram webpage http://www.osram.co.uk/osram_uk/tools-and-services/services/dimming-conformity/index.jsp they pass the responsibility onto you checking the spec for individual products.

LED lamps can be dimmed with a multitude of leading edge or trailing edge dimmers available on the market. OSRAM provides a list of suggested dimmers for each product. You can find this list in the technical information sheet on each product side in the product catalogue.
It can be the case that LED's are to small a load for the old dimmer to work correctly and you can get a flicker effect similar to when you have insufficient load with traditional GLS lamps off a dimmer. The days of simply getting a dimmer with the correct wattage for the number of lamps connected have passed. Going back to den123 original question, it is impossible to answer without verifying the types of lamps you want to dim, due to the reasons given above.

Doc H.

 
Cheap dimmers are best avoided unless you know that the particular make and model is okay from experience. They're often noisy acoustically with an audible buzz, they're prone to EMI and RFI problems plus they tend to run warmer with less efficient heat dissipation than the more expensive ones so therefore their MTBF is shorter. Buy cheap, buy twice is a phrase that springs to mind

on a slight tangent, I`ve been told that if I replace normal bulbs with dimmable LEDs, I will need a special type of dimmer switch? Is this necessary?
Some LED's, depending on their internal electronics, will specify that the dimmer must be leading edge or trailing edge, just check the manufacturers info before you specify one.
 
thanks for the replies everyone - So I`ll check manufacturers info.

Can anyone explain to a thick plumber what leading and trailing edge dimmers are?

to a thick plumber??

probably not then!

But the basic concept could be summarised as:-

Our electricity is an ALTERNATING CURRENT...

it rises and falls from 0v to a peak +ve voltage back through 0v to a peak -ve voltage then back to 0v..  (AKA 1 Cycle)

The nominal RMS voltage should be 230v +10% - 6%   (AKA somewhere between 216.2v & 253v)

The frequency of our electricity is 50Hz  or 50cycles per second..

To get the lights to dim we need less of this voltage to get to the lamps...

Various methods can be used within dimmers to reduce the voltage passing through,

by cutting off part of the alternating cycle..

some of the electronics in the dimmer could respond to the leading or trailing edge of the alternating cycle as the voltage naturally rises and falls every 0.02 of a second (50Hz)

Any further info is probably best if you do a search on leading & trailing edge on Wikipedia or similar.. 

Cuz I am not typing any more!

:coat

 
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