High temperature bulb fitting

[bergentrude]

Hi Guys,

I'm hoping you can help. I've bought in some ceramic heat bulbs in from China that are slimmer than the ones already on the market. I have them in 60, 100 and 150W, however after testing at full heat the 150W especially appears to be burning the inside of the ceramic fitting. It's the little metal conductors that appear to be burning. The 100W does appear to be turning colour ever so slightly, whilst the 60W looks fine. As they are smaller in height, it appears the heat is rising directly into the socket and causing an issue.

In this picture you see where the elements are slightly burnt.


This picture shows no burning.


This is the holder and heater in use. They are to be used in tanks for animals that require warmth.


I would like to ask, does anybody know of any different types of fittings that can withstand the extreme heat that these bulbs give off?

Thoughts are much appreciated.
Thanks

 

[malcolmsanford]

First I would be asking before you got these lamps, what lamps did you use before and was there any discolouration to the holders then?

If no then you need to really look at the lamps rather than the holders. There is a subtle difference in the ES27 we use in the UK and the thread to the American E26 (MES)

You may find that this could be causing your problem. It may also be that the lamps are poorly made,or that the lamps are indeed a higher amperage than indicated.

 

[bergentrude]

Hi Malcolm, they are the standard E27 fittings, but this is not something I can compare before. These are new products I was hoping to launch to market. The wattages of the lamps and the stability all appears to be ok. I feel more than anything the fittings just cannot withstand the extreme heat, as the bulbs are made shorter, more heat is rising into the holder rather than longer bulbs where the heat dissipates elsewhere.

 

[malcolmsanford]

I suppose we could guess and counter guess all day really. It might be exactly what you said or it may be something I said or perhaps a combination of them all or 2 or 3 etc etc.

The existing lamps I assume had no detrimental affect so it is something in these new lamps that is causing the problem.

You can only eliminate things as you go along. You can check the threads with a micrometer to see if there is a difference, you can check if the lamps are loading over their rating with clamp/measuring meters on the cable, and you can check the heat foot print of both lamps with an infra-red camera

 

[bergentrude]

Hi Malcolm - the problem is clear and it is down to the height of the lamps. The slimmer lamp as you see in the picture pushes more heat into the fitting. The temperatures are far hotter and the fitting cannot withstand it. Of course, initially it means I cannot use this wattage heater, but my main question is, does anyone know of any E27 fittings that can cope with much higher temperatures?

 

[oldtimer]

Look at this another way first of all what environment to to want to heat ie a horse stable also this is in my view a poor design first of all I do not think it would comply with our safety standards why you ask well the heat should be directed away from the light fitting and plus it also tells me if its hot enough to damage the ceramic light fitting even if you are using heat resistant flex this is still a safety issue with regards to injury to Joe Public or the animal you are trying to keep warm if they touch it.

Say for example it was a stable then you would fit a low wattage tube heater with a control thermostat and a protective cage around the heater so there would be no way the animal or human would get hurt with regards to heat.