I bought a non-contact voltage tester and socket tester a little over a year ago. The socket tester hasn't let me down yet, but I haven't used it that often either. The non-contact voltage tester (VD6504) is junk in my opinion. I always felt like it wasn't working as intended, like it was too sensitive. But I needed an accurate measurement when trying to find the burned out light in my Christmas garland. About 18 inches from the light it went out. The same happened near sockets. This might work for some people, but when you have circuits close together you don't know if one of them has no power. .Of course you can disable both circuits or all circuits, but then you don't need this tool. Sperry received a warranty replacement that shipped promptly (love that from them). The problem is that now it just turns itself off. about 3-4 inches from the outlet. I was able to use my father's non-contact Klein tester. It is able to differentiate the power on each side of the cable (and what, 1/8"?). It helped locate my problem. I will not ask for any OTHER warranty item as I don't want to that they're losing money I'll probably look at Klein or Fluke.
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