Q: Please explain the N-PE-L lights. When all three are lit, this is incorrect. Why? Often, socket testers have three lights but they're not labelled because they don't relate to the pins. If you're going to label the pins, then you probably want green/red LEDS that will be green when that pin is correct and red when it's not. (otherwise seems better to remove the labels) Is there a link to the user manual?