Fix wire/cord lamp - Don't know polarity

[evanston]

The wire of my lamp got cut and I would like to fix it by plugging in an extension cord. I understand the following tutorial:
https://www.youtube.com/watch?v=lnncXVpoL3g

But I don't know how to determine the polarity of the two part of the wire (+/-) in order to fix it. There is no ground. There are no colors either. Please help!

 

[Marvo]

Where is your switch? If those wires go directly to the lamp holder and if it's a bayonet fitting then polarity isn't an issue, you can connect either way.

If you have a switch somewhere then you need to switch the live and if the lamp holder is a screw-in type then the live should be connected to the center part and the outer thread that the lamp screws into should be neutral. You'll need a tester/multimeter to prove polarity.

 

[evanston]

Marvo, thanks a lot for your response!

I have edited my post with more information. The switch is on the rod of the lamp (picture available) and the holder is a screw-in type.

What do you mean by switching the live (I am a complete beginner, I apologize) and how do you do it?

I have an old (!) multiplier handy (picture). I haven't been able to determine the polarity of an outlet with it (I could not capture the sign +/-). Is it possible with this type of devise and what is the proper setting?

As mentioned above, I am a complete novice so if someone can provide me a detailed procedure, it would be highly valuable. Thank you in advance!

 

[ifindoubtdont]

DO NOT USE THIS METHOD OF TESTING ON ANYTHING LIVE OR PLUGGED IN. Without the correct test equipment and knowledge of how to use it, it could be dangerous. Right, warnings out of the way, the equipment you have should be able to test continuity. The lamp (bulb) you are showing is an ES (Edison Screw) type and the centre nipple at the screw in end is the part that should connect to live. Now to the light fitting,with the red (+) probe find the tong that the centre nipple would touch and press the probe firmly on that. Now to the wires, pick either one and press your black probe(-) on the bare wire, what you are looking for is movement of the needle, if it doesn't move at this point operate the switch on the lamp and re-test, still doesn't move, choose other wire and repeat test sequence. When you are satisfied that you have the correct wire and that by operating the switch you get movement/no movement then this is your live(+) wire and should be wired to the fused side of the plug.

 

[telectrix]

think OP is in U.S.A. won't have fused plugs .

 

[ifindoubtdont]

I think you might be right Tel, the only Evanston I could find was in Illinois.

 

[telectrix]

ain't google great!

 

[Marvo]

If it's on a 2 pin USA plug then the plug can go in the socket either way around so don't worry about polarity and don't worry about switching the live (hot) wire.