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David wrote:

putting a pot over it and preventing insulation coming into direct
contact
will obviously keep it much cooler than if the insualtion was in
direct
contact with the lamp. That is the primary goal in doing it.

Now that I disagree with, I don't believe the flowerpot will keep the
lamp cooler. How does it do that? With a flowerpot over the lamp
there will be *less* air circulation than without, how is that going
to keep the lamp cooler?

The flowerpot may make things tidier and/or more fireproof but I
really
don't believe it will keep the lamp cooler.

--
Chris Green

If you compare a lamp with insulation over it and one with a pot over it
and
eth insualtion held back 10-15 cm then the one with the pot will be
cooler
in comaprison.

Have you measured that? I really don't see how this can be true, do
you have any explanation as to why it should be cooler? There is
absolutely nowhere additional for the heat to go in the case where the
lamp is in a flowerpot so how can it be cooler?

--
Chris Green

The lamp will warm up the air around it and the warm air will rise.

As the warm air rises up it comes into contact with flower pot and the
flower pot then heats up.

the flower pot now gets warm and warms the air around it.

and so some heat from around the lamp is removed

Have i measured this with lamps. No I've no desire or need to do so.

I have looked the heatsinking requirements and thermal characteristics of
semiconductors? yes on quite a few occasions.

Lets say I have a component that must dissipate a fair amount of power, a
few watts say. Now if this just sits on a PCB board it gets pretty hot, the
internal temp may easily be about 125C, If I tightly pack other components
around it (i.e provide some insualtion) then it heats up to 175C and fails.
If on the other hand I add some heatsinking then its operating temp will be
much lower.

If you surround anything in insulation then obviously it will retain more
heat than if there is any sort of air gap.

Given that this is the whole point of the insulation it's something that
just seems common sense, I can't really fathom your problem with it. You do
not need to have an massive air flow to get heat transfered. As above you
will have heat transfered from lamp to air to pot to air. Not the most
effiecient heatsink in the world but when compared to 150mm of rockwool
there will be a difference.

regards

David