Are common house electrical wires 75C?
Answers: You in truth don't have ample information here to answer the question definitively, but I'm 99% sure you are okay. The tentative outside fixture is probably less than 150W on a120V circuit next to less than 1000W of existing nouns on the circuit. If the existing circuit already has 1600W of nouns on a 20A breaker or 1200W of load on a 15A breaker, you obligation new flex to handle the extra load, regardless of the warmth rating of the wire. The line rating is how much the temperature of the chain rises above the outside ambient air warmth when carrying the full rated current. If you are not carrying 20A contained by the wire or you live within a really hot place like Las Vegas, the heat of the wire get nowhere near its melt point. Which is what determines the wire rating warmth rating which is based on a 30 level Centigrade ambient air warmth. Even if the wire is 60C flex, it is tough to raise the flex temperature that much by current flow. Additionally, mature wire be designed conservatively. What was call 60C in the 1950's is more approaching 75C now. Except for the few previously tabled caveats, you are fine.
unanimously the wire within those houses was TW of TH rope. they were rate at 75deg. you should be fine.
The new street lamp fixture will draw about matching amps, so if it worked before, it will still work. The electric wiring should be fine. Don't worry.
The 75C is the heat rating of the insulation on the wire. TW and UF wires are rate at 60C (140 degree F). TH cable is rated at 75C (167 amount F). The wire within your older house is most plausible a 60C wire. The fixture businessman had the fixture tested and tabled (think UL) with a 75 level wire.
Most electrical codes require electric wiring for lighting to be rated at 90 degree C.
Make sure the fixtures either hold insulation where it mounts to the outlet and/or the muted bulb stood off the dais by the design of the fixture.
Coach Lamps are designed this way and would be just right for your purpose. This type of design keeps the roast from the building wiring.
Purchase just fixtures that are rated for outdoor use.
Good Luck
Joun Himself is on the money. FYI, it is the boil that the bulb produces that can "cook" the insulation that is on the wires. It may enjoy come with some sort of insulation to prevent this from scheduled. DON'T, I repeat, DO NOT DEFEAT IT'S PURPOSE!
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