growler
Senior Member
- Location
- Atlanta,GA
It's not a matter of polarity, it's a matter of reducing shock risk. For example, by making sure the neutral is the conductor supplying the screw shell of a lamp or fixture socket, the risk of shock while changing a bulb is greatly reduced.
A partially-unscrewed bulb's screw-shell is exposed while it's still in contact with the socket's screw-shell. The ribbed conductor of the lamp cord is connected to the screw-shell, so it will be connected to the neutral via the wide plug blade.
It's hard for me to imagine working on equipment these days without my trusty no-contact voltage sensor. Yes, I do test on known live circuits quite often.