Bulb rating (7)
I believe the answer is:
wattage
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bulb rating</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for wattage that I've seen before include "Electrical power rating" , "Amount of electrical power" , "Light bulb power rating" .)