Can't say that I know the law on this but the bottom line is that backstabbing was okay for just the convenience outlets that were typically for a lamp, or such device. These days when we are using extension cords and drill motors that can cause heating up of the contact point in a backstab application it causes a deteriorating effect on the metal in the receptacle. The metal heats up and over time can warp and the loose connections occur and the arc fault breakers trip.Just curious if this practice is still out there. Recently talked with a new hire who has been trained in this fashion. Thought this went out back in the 90's.
aren't those contacts tested in a laboratory...ACA said:There are still transformers with PCBs, and asbestos covered pipes as well. Bring your new hire up to speed. Back stabbing a receptacle gives you very little contact surface and will cause the connection to heat up under heavy loads.
maybe the fault current would be to high for a back stab plus it is probably cheaper to just add lil piece of threaded metal then to an extra back stab feature..IslandGuy said:Yes they are. Which makes me wonder: Why can't you also stab the ground?
Supposedly of preventing backstabbing old aluminum, but where you see 12 you see the most loading. And the most failures of back stabbing occur on heavy loads where the ooutlet goes under constant heating and cooling.it probably cost more to manufacture 12 slots when most of the wiring in a home is 14....just my guess..it all boils down to money...