I examined rather closely the NEMA L5-30 socket and pin design and now want to show the SmartPlug 30A pin and socket. It's only fair right...?


What jumps out to me is the sheer contact area made by the SmartPlug pin and socket. Not only can the clamping spring be longer but because the pin and socket are FLAT there is a ship load more contact area.



Once plugged in and locked a SmartPlug 30A or 50A male/female socket combo CAN NOT MOVE side to side or up and down. This was a major part of the design criteria for this system..


This essentially means that no torquing or unintended loading of the spring clamping mechanism, beyond the design criteria, can occur with the SmartPlug. It does not take an engineer to see that the spring clamp can remain tighter, and in design spec for FAR LONGER, with the SmartPlug than it can with a twist-lock. It can remain in spec far longer than a twist-lock because the twist-lock allows for odd angles, twisting, unintended odd angle loading and torquing and expansion/stretching of the clamp mechanism all due to its poor design.


Sure in 1938 perhaps the twist-lock plug was the cats meow for industry and factories. Today, in 2014 we CAN do better and Smart Plug has done better..