Failure Mode of GFCI

Discussion created by mhl24 on Nov 3, 2016
Latest reply on Jan 19, 2017 by shooter

I disassembled a "failed" GFCI.  (If you've not done so, I strongly encourage it....they are  complex.) There are "springy" metal contacts that open when the GFCI trips.  On both sides (hot and "neutral") there was evidence of considerable arcing and heating.  There was extensive pitting....and i'm inferring that was caused by arcing.  Heating is evidenced by small amount of melted plastic where the "springy" metal contacts rest on a plastic wedge.  (The wedge slides to open the circuit by raising the "springy" metal contacts....away from a mating contact.)

MY QUESTION:  What could have caused the arcing?  My only conclusion so far is that something that was drawing significant current caused the GFCI to open.  Any other thoughts??  #GFCI