Down Lights

skystorm · Oct 14, 2009

Hi All
Just a qiuck question got a phone call,About down lights in corridor when they turn them on they will only stay on for few min and go off, if you turn them off and back on they will do the same

Yooj · Oct 14, 2009

What type of lamp are they...sodium discharge or anything like that?

Need a bit more information, like how they are switched, are they on some type of timer, etc.

Yooj

Mac · Oct 14, 2009

Transformer problem

sparks1234 · Oct 14, 2009

Are we talking low voltage here?

skystorm · Oct 14, 2009

Hi Just got back ,Had a look ,3 sodium lv lights with a transformers can only get to the light and transformer , Stay on for a few seconds and start to dim out like the power is getting drained out ( Had a loft coverted to bedrooms )

beaver74 · Oct 14, 2009

skystorm said:
Hi Just got back ,Had a look ,3 sodium lv lights with a transformers can only get to the light and transformer , Stay on for a few seconds and start to dim out like the power is getting drained out ( Had a loft coverted to bedrooms )

LV sodium ???????

Yooj · Oct 14, 2009

Hi, Been a while since I have done any Sodium lights, and I am not entirely sure of the set-up of the lights that you looked at today...however, the order of troubleshooting should be (from memory):

Replace lamp.
Replace ignitor (where used).
Replace both ballast and capacitor.

Other things to consider are: Are the lamps blackened....do any of the other components appear blackened or overheated...all I can remember now, though it did tend to be the lamps that were at fault 80% - 90% of the time.

Finally, take a note of the manufacturer of the units, and give them a buzz to find out whether they have any technical manuals on units...if nothing else, it will give you replacement part numbers, but it might give you some useful troubleshooting tips.

Yooj

skystorm · Nov 1, 2009

Hi
Been doing this when the sparky first put them in
Done everything in the book apart from rewire still dimming out any more idea,s would be gratefull

Bright Sparks · Nov 2, 2009

Are you sure they are LV Sodium ? and not Low voltage Halogen ?

If they are low Voltage Halogen, it sounds like there is an issue with the transformers. It could be any number of the following;

1. Over heating - are they covered in insulation ? or in a high ambient temperature ?
A. Most run at at a case temperature of around 80 Deg C but an ambient working temperature of about 45 Deg C. Insulation on or close to the transfomers will no allow the heat generated to disapate and cause it to shut down. (If it is of a reasonable quality it will have a thermal cut out and on reaching working temperature will start to work again).

2. Over load - The wattage (Va (voltage/amps)) of the transformer could be exceeded. Check what lamps you have against the values on the case of the transformer. Again the transformer should have 'Overload protection' which would shut it down to protect it. It might be that 2x 35w lamps have been wired on a single 20-60va transformer, after a while in may shut down.

3. If they are on a dimmer, it may be that they are underloaded, and being dimmed, but what you have described doesn't seem so.

Hope this helps.