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This is a recessed light I pulled out of my ceiling. There is a black cylindrical thing attached to the junction box and wired in series with the live wire to the bulb base. What is it?

The junction box and the black thing are both an integral part of the light fixture, ie they came with it.

The cylinder has "A10A9 Mexico" marked on it. This is in NJ, USA and the light fixture is probably around 1970s or 80s era.

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Harper - Reinstate Monica
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jay613
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1 Answers1

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It is a thermal protector for a recessed ceiling light. It will cut out the light if the temperature of the outside of the fixture exceeds the rating of the protector. All UL approved fixtures will have them. If the protector fails, in many cases,the bulb will turn on and off signaling a bad protector.

enter image description here

Picture from Lighting Supply.

JACK
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