If you want a truly SAFER shore power system PLEASE go spend the money on a Smart Plug cord and receptacle.
The current standard we use is HORRIBLY unsafe IMHO.... It is nothing more than a left over, adapted from land crappy standard that is not well suited at all to a marine environment.. The NEMA "Twist-Lock" standard is outdated and less safe than it should be.
Be smart install a SmartPlug!!!!!!
See article here: SmartPlug vs. 1938
Disclaimer: I have ZERO affiliation with SmartPlug. I don't even have a direct commercial account with them. I do however believe in SAFETY FIRST!!