I have a quick question. I have OCD-like tendencies that require me to check plug sockets and power strips daily to make sure they are fully inserted. Now, the house is correctly wired, no surge strips are overloaded beyond what they are rated and there are never combustible materials near the electrical outlets. If a plug happens to have the polarized prongs showing (e.g. not fully inserted/halfway in) is there any risk of fire? if so how big of a risk? I know of the shock hazard, but not of the fire risk and there seems to be no data available online of whether or not a “non-fully inserted plug” causes fires.
If having the plug partially out of the socket was a huge risk, lawyers would be lining up to file lawsuits and the government would ultimately get involved.
Our plug/receptacle standard here in the U.S. is far from perfect. But it results in very few fires. There are other things much more worthy to worry about, if you’re the worrying type.
Well, a partially inserted plug would increase the risk of a piece of metal somehow jamming in there and sparking, but that should trip the breaker anyway. If the plug was only in just a bit, barely enough to hang on, I suppose a heavy current draw could cause localized heating of the contacts. This sounds like a good time for a non contacting thermometer and a bit of home research. Report back!
Well then the general consensus is that I shouldn’t worry, probably at greater risk of dying in a car accident than a plug not being fully inserted (the outlets are all new, UL certified anyway). Thanks! and to mixdenny… I have a nubee infrared contactless thermometer, i’ll give it a shot. Thank you all for your help, and of course more replies are awesome!
A plug that is making a very poor contact could lead to two problems:
Excessive heat at the contacts due to high contact resistance (P = I[sup]2[/sup]R).
Arcing.
Generally, #1 is only an issue for high power loads. But when it happens there is often some negative feedback that “fixes” the problem: as the contacts heat up, the metal softens a bit, thereby increasing the contact area and thus reducing the contact resistance (and thus reducing the temperature).
#2 is a more serious problem. I am not sure how common it is for arcing to occur at the matable contact surfaces. I’ve only seen it occur where the wire terminates into the back of the device.
If you’re concerned about “loose sockets” causing a fire, you can test each receptacle using a Receptacle Tension Tester.
Ever notice how all the receptacles in a hotel room are really loose? That’s because they’re used so much; the greater the number of mating cycles, the more the spring force decreases. Yet you don’t often hear about fires in hotels due to loose contacts in receptacles. But then again, perhaps it’s because the loads that are plugged into receptacles are usually very light (e.g. cell phone charges).
Nice toy.
But I can see in the near future as these sell, health care facilities will be required to test every outlet and keep a record of the tests. And a comparison of the readings year to year. At some point if the outlets tests below a set reading (set high to insure safety) it will have to be replaced with a new certified outlet.
A hospital will have to hire a team of men to continually go through the hospital testing the outlets and office staff to record the readings. And the new “certified” outlet will probably cost $10 to $20 each.
There is a reason that health care cost are so high.
I’d be far more concerned about the overuse of extension cords and power strips than I would of slightly loose outlets. Way more fires have been caused by people putting carpets on top of extension cords than from a wobbly plug.
Just putting this out there to clarify. I had installed them myself, and properly (meticulously), so the outlets themselves are not loose (they are UL listed, screw type), and do hold all plugs inserted tightly, the outlets themselves are solid. I was more concerned with, lets say I pulled a power strip, or cord or something on accident and it knocked a plug or two a little loose where the prongs would be visible. Again, no combustible materials nearby, power strips have less than half of what they are rated for plugged into them, and the power strip sockets are tight too.
Trips and falls are a much more likely cause of home accidents, along with accidental poisoning. Make sure there are no slippery floors, toys lying about, or loose rugs, and that all household chemicals are kept in their original containers.
Reading these replies has nearly eliminated my OCD, haven’t worried about plugs being inserted or anything lately (since the night I got the first reply). Thank you all! It eased so much pain.