1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Downlighters problema

Discussion in 'Electrics UK' started by breen77, 25 Feb 2013.

  1. breen77

    breen77

    Joined:
    25 Jul 2011
    Messages:
    33
    Thanks Received:
    0
    Location:
    Belfast
    Country:
    United Kingdom
    Can someone help.

    I have many downlighters installed throughout my house as I built it not physically but from scratch.

    The problem with the downlighters is that a few have blown but when I replace the bulb it does not work??? Would there be anything wrong with the downlighters??

    The next stage is to try and disconnect one that works and see if that proves anything.

    Does anyone have any ideas or ever come across this?
     
  2. Sponsored Links
  3. sparkybird

    sparkybird

    Joined:
    19 Jan 2005
    Messages:
    1,171
    Thanks Received:
    41
    Country:
    United Kingdom
    if they are 12V lamps (bulbs) then it's probably the transformers that need replaceing
     
    • Thanks Thanks x 1
  4. breen77

    breen77

    Joined:
    25 Jul 2011
    Messages:
    33
    Thanks Received:
    0
    Location:
    Belfast
    Country:
    United Kingdom
    Why would this be? The lights are in hall and landing so never constantly on just switched on and off. The never stay on for long periods.

    Which part is the transformer? Is that the white box that the mains cable connects to?

    Where can I get them? How long should they last?
     
  5. STI

    STI

    Joined:
    5 Aug 2009
    Messages:
    426
    Thanks Received:
    27
    Location:
    Birmingham
    Country:
    United Kingdom
    When you replaced the bulbs what were the pins like, very thin or like a rounded t shape.
    If thin then v likely to be a 12v. The transformer is usually an oblong box with writing on it stating its power rating amongst other things.
    Why do they blow , because they can. Often you can find where they connect to the light fitting the terminal box has overheated, usually due to a poorly made connection.
     
    • Thanks Thanks x 1
  6. breen77

    breen77

    Joined:
    25 Jul 2011
    Messages:
    33
    Thanks Received:
    0
    Location:
    Belfast
    Country:
    United Kingdom
    Yes they are small thin pins.

    Yeah know the transformer box now how do I make it a better connection? Where can I get replacements?

    It doesn't mater how long they are switched on for they can still overheat?? Can I replace them with the rounded T shape connectors?
     
  7. sparkybird

    sparkybird

    Joined:
    19 Jan 2005
    Messages:
    1,171
    Thanks Received:
    41
    Country:
    United Kingdom
    12V transformers here

    http://www.tlc-direct.co.uk/Products/LTYT50.html


    You may be able to change them to GU10's (mains halogens - I'm guessing this is what you mean?) - but you will need to be able to by pass the transformers and it will depend on the type of light fitting you have - mains tend to require an earth.....
     
    • Thanks Thanks x 1
  8. Sponsored Links
  9. breen77

    breen77

    Joined:
    25 Jul 2011
    Messages:
    33
    Thanks Received:
    0
    Location:
    Belfast
    Country:
    United Kingdom
    Will probably keep the type I have.

    So I can just replace the transformers and all should work again? Will order 1 to test.

    What should be the life span of the transformers?
     
  10. Taylortwocities

    Taylortwocities

    Joined:
    28 Jul 2006
    Messages:
    20,550
    Thanks Received:
    2,132
    Location:
    Oxfordshire
    Country:
    United Kingdom

    They are electronic items. They can last 10 years, they can last 10 minutes.
    Cheap is never the best plan/


    Back in the good old days each room had one light bulb.

    If a bulb went every 2-3 months you didnt think about it as you only have perhaps 8 lamps for the whole house.

    Now you have maybe 12 lamps in a single room and, even with a modest failure rate it will seem to you that the lamps keep blowing all the time.

    That will serve you right for contributing to global warming by using 300watts of energy to light a room that can adequately be lit by a single 60 watt old style light bulb. (Or even better a single 11watt energy saving lamp).
     
  11. Monkeh

    Monkeh

    Joined:
    25 Jan 2010
    Messages:
    4,149
    Thanks Received:
    329
    Location:
    Cornwall
    Country:
    United Kingdom
    An 11W CFL isn't adequate to light my loo, let alone any inhabited room.
     
  12. ericmark

    ericmark

    Joined:
    27 Jan 2008
    Messages:
    18,614
    Thanks Received:
    1,746
    Location:
    Llanfair Caereinion, Nr Welshpool
    Country:
    United Kingdom
    I was pleasantly surprised when I tried some of the LED lamps. Far better than expected. With the folded or coiled compact design of florescent or cold cathode lamps there is a huge difference between the designs. Where the control gear is separate from the tube high frequency inverters can be used to control the lamps which in turn means they are far more efficient and the tubes last longer. So a 22W 2D ceiling lamp with an electronic starter (HF) will in general give out far more light than a 22W CFL where the control gear is built into the lamp.

    As far as the 50mm spot lights go there are two main types the 230v GU10 which will allow swapping between CFU (Cold Cathode), LED, and Quartz Tungsten with ease and the extra low voltage type which are sub divided into two main types.

    The old types used a transformer and one can swap the lamps to LED from Quartz Tungsten without any real problem but the whole idea of the low voltage was to maintain the lamp at a very controlled temperature. Two hot they burn out and also too cold and the tungsten is deposited on the quartz and again they burn out so today simple transformers are no longer used instead an electronic switched mode power supply is used. These often called transformers have a minimum output as well as maximum and so you can't swap to LED without also changing the transformer.

    The extra low voltage (12v) also have a problem with the pins where the holders over heat and contact with the pins is lost. Unlike the low voltage (230v) GU10 and GZ10 where the dichroic lamp will only fit the GZ10 type with the extra low voltage MR16 the dichroic lamp can be fitted in error to the fittings where there is no allowance made for the extra heat at the back of the lamp. As a result they over heat.

    When any tungsten lamp blows one can get ionisation as it blows and there should be a built in fuse however this is not always the case and the cheaper inverters and dimming switched can fail as the lamp blows if there is no protection built in.

    Quartz lamps should not be dimmed although there are dimming units that will work with them. This is because the temperature is so important to give long life. However there is often no warning about dimmers shorting the life on the dimming switches. With non quartz they in fact can increase the bulb life.

    Today with the better LED and Cold Cathode spot lamps there is really no reason except maybe in the bathroom for using the extra low voltage lamps. However our rules since the 1960's require earths to be taken to the light fitting even if not used. This means changing from ELV to LV can also mean changing cables. Or using double insulated units and turning a blind eye to the rule on earth wires.

    There are alternative units to replace the low voltage inverters that will work with LED lamps but it does in the main mean you can't return to using quartz halogen tungsten lamps.

    One other problem with the ELV is lamps come from 10W to 50W with the same connections so where designed for 10W it is easy to overload the inverter and where designed for 50W you can under load the inverter.

    With both MR16 and GU10 there are many angles of lamp again so easy to get a lamp which will physical fit but does not do the job as the angle is wrong. They are spot lights and work well as bed side lamps or lighting pictures on the wall but as general lighting they need to have the light reflected off a white surface so changing the wall paper to a pattern can result in a very dark room looking more like a planetarium.
     
  13. ban-all-sheds

    ban-all-sheds

    Joined:
    27 Aug 2003
    Messages:
    69,782
    Thanks Received:
    2,858
    Location:
    London
    Country:
    United Kingdom
    Shame you didn't get somebody who knew what they were doing to design the lighting for you.
     
  14. djt205

    djt205

    Joined:
    19 Sep 2012
    Messages:
    5
    Thanks Received:
    0
    Country:
    United Kingdom
    @BAS I always think of you when I see these things... you are spot on (get it) ;)
     
  15. DIYnot Local

    DIYnot Local

    Joined:
    3 Sep 2019
    Country:
    United Kingdom

    If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

    Select the supplier or trade you require, enter your location to begin your search.


    Are you a trade or supplier? You can create your listing free at DIYnot Local

     
Loading...

Share This Page