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I'm really intrigued by the label on a new lamp. It says:

Caution: To reduce the risk of fire, use MAX 60 watt type A lamp OR use MAX 10 watt self-ballasted LED lamp or lamp adapter.

Now I didn't get where I am today by going around exceeding the wattage specified on my lamps, but that does seem kind of odd. If it can handle the heat from a 60 W incandescent bulb that it emits most of its energy as heat, why can't it handle a 15W LED that puts out more light but uses less power? Do LEDs run hotter per watt? Hotter just in the socket? Is it backdoor warning me not to blind myself with a bulb that is too bright?

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    \$\begingroup\$ Just a guess without context you have and we don't. LEDs suffer in performance and lifetime if they don't have adequate cooling. Maybe the fixture provides enough cooling for a 60W bulb (where the problem is setting fire to things) or a 10W LED (where a 15W LED would cook itself) \$\endgroup\$
    – user16324
    Commented Sep 4, 2021 at 23:53
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    \$\begingroup\$ It's not that LEDs run hotter per watt, but rather where that heat is generated. In a standard incandescent bulb, all of the heat comes from the filament, and the IR radiation (heat) radiates away from the bulb's filament and glass housing. In an LED, the heat is mostly generated in the base, by the electronics there, and it is much more difficult to remove the heat from the base than from the bulb itself. This is one of reason most LEDs are not recommended for used in air-tight enclosed recessed fixtures. \$\endgroup\$
    – SteveSh
    Commented Sep 5, 2021 at 1:14
  • \$\begingroup\$ I like Stevesh comment. Anyway, if you post a photo of the device, we could give a better opinion. \$\endgroup\$
    – mguima
    Commented Sep 5, 2021 at 2:50
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    \$\begingroup\$ I believe that, with incandescents, the rating is based on the power that the fixture can safely dissipate without overheating. With LED bulbs, there is no issue with the fixture overheating, but the bulb itself can overheat at a much lower temperature due to heat not sufficiently transferring out of the fixture. \$\endgroup\$
    – user80875
    Commented Sep 5, 2021 at 4:43
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    \$\begingroup\$ @SteveSh That comment is answer-worthy! \$\endgroup\$ Commented Nov 2, 2021 at 21:03

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