I am replacing a bathroom light and when I did the tear down, I forgot to label (I know, my fault) Anyway, someone bought me a multimeter and have no idea how to use it. It's the GE2527 - has a dial to DCV ACV DCA BAT OHM. It has a red and a black line to be plugged into it.

I just want to find out which of the two wires (1922 house-no ground and not romex) is to attach to the white and black wire of light fixture. I know I have a 50-50 chance that I connect it to the correct one, but I'm not sure I'm willing to risk it.

 

Start with the ACV 250 scale. That will be what you use for most things. Unfortunately, this multimeter isn't of much more use to you than a $2 neon circuit tester. In fact, unless you understand phantom voltage, it could be of less use. For now, there are only two voltage readings that you should be concerned with: (1) Anywhere between 110 and 130 should be regarded as 120. (2) Anything less than 100 should be regarded as zero.

If you have no grounding wires, then put away your multimeter. It isn't good for much of anything to you. Instead, go to Home Depot and spend $15 on a voltage "tick" tester. While you are there, spend another $8 on an outlet tester (the kind with two amber lights, a red light, and a button). Then buy a $2 neon circuit tester, and you'll have everything you need.

For your current project, the tick tester is all you need.

 

Thank you, I'll return this one and get the others.

 

Keep the multimeter. It'll come in handy later. It's good for determining whether a voltage is 120 or 240. And every once in a while, the ohmmeter comes in handy for identifying a switch loop.