Here we have a picture of a old residential outlet. This style of outlet was installed before we used the grounding. Grounding was added to electrical systems to improve the safety in the 1950's. This outlet was wired into an old knob and tube system. Knob and Tube wiring does not have any type of ground wire to accept modern plugs. The best way to handle this type of old electrical system is to re-wire. We can also replace this old type of outlet with special non-grounded outlets. You not want to install an outlet with a ground hole in the face. That would only give you a false sense of security but not a ground.
It is just a outlet with a special design thats all.
ReplyDeleteno, there actually is a purpose to the design: http://www.plugsocketmuseum.nl/NorthAm2.html
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