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Cardboard insulator? Answered

Thank you so much for these tutorials.

These cardboard insulators are almost never seen in europe, is there a reason? Is 110volt more suitable than 230v maybe? I am in Europe.

Do you think the electricity travel cardboard in the cardboard? My nations authority that decide standards for all electric products question the cardboard when i asked them, they never seen it.

I am experienced with these sockets by now, but I got a shock when changing bulbs whilst the plug was in the wall the other day, metal socket with cardboard insulator. And I cant find the reason for it, the insulator on place and intact, the wires not too long so the bottom of the socket were touching either.
In case I put electrical tape on the inside of the socket wall, between the insulator and the metal socket.

Another question. Depending on how the connector plug is plugged into the wall the threaded white metal part on the socket might be the hot/live part rather than the neutral. Its slightly more risky if the threaded socket base is the hot one, but you cant really know unless you have special earth plug in usa or when using any plugg in the UK. Other non-earth plugs and any standard europe plug with only two pins are more risky.
Does it matter do you think?


Paige Russell

Best Answer 2 years ago

Hi flower2222,

I'm afraid I don't have an answer for the 110volt vs. 230v, but I do know that every socket has to have some kind of insulator if the outer casing is metal. On any metal European sockets I've seen, there has been a ceramic insulator, or rather the socket itself is ceramic with the metal casing covering it.

Sockets made from other materials like porcelain or phenolic don't require an insulator because those materials aren't conductive. (Cardboard is also non-conductive.)

Regarding the shock you received, this can happen if:

- Your lamp is plugged in and the socket and/or switch is in the on position (which means that electricity is actively flowing through the socket.)
- your fingers were touching the metal threads of the bulb as you are screwing it in. The threads of a bulb complete the electrical circuit.

Try to only hold the bulb by the glass, and the lamp below the socket, when screwing in a bulb.

If you received a shock from the outer metal shell of the socket on a lamp you made yourself, this means that the outer shell is coming in contact with a live wire and needs to be fixed. The cardboard shell does not conduct electricity, so it would be happening elsewhere. Feel free to send me clear photos of how the socket and plug are wired (and switch if one was added) and I can help solve the mystery.

Regarding your question about plugs, most modern two prong plugs in the USA have one that is wider than the other (this is the neutral) so it is impossible to put the plug in the wrong way. Having said that, non-Polarized plugs are still sold and if everything is wired correctly and safely, there isn't any risk if the prongs are reversed when plugged into the wall outlet.

I hope this was helpful! Please let me know if you have any more questions. :)


flower2222Paige Russell

Answer 2 years ago

Wow. You are so clear and methodical with your answers and guides. Ty

I have been wiring many sockets with cardboard insulator and brass shell as of late, I use a cheap Chinese one and that in it self is concern. The same type you will find when googling images of "brass lamp socket" and I figured after making 10 lamps that if one press hard down when changing bulbs there is a chance of exposure since the socket glides down and leaves the cardboard shell, and thus the metal sockets connects with the live wire if there is only few millimeters of wire exposed.

My solution before is that I I mount the wire around the screw with a loop that is twined.
Then put electrical shrink tube as far up the wiring as possible as seen.

Now I will try tape over the live part like this in the image linked below, same also attached.

Do you know how bad or good such a electrical-tape solution is?

Any wise words?