Just to add to the information database here, Paramount has been making specialized PC cords with a similar voltage protection setup for years too. I went the the Wein when it first became available many years ago. There are several different models so be sure you get the right one for your setup. Your other option is to forego using those pesky, always act up when you need them most, PC cords entirely and go with an Infra Red or radio slave. (then all you have to worry about is the batteries dying on you, a shoe breaking off, poor electrical connections, dropping them, banging them into something or that someone else is on your channel) No matter what route you go there are always going to be bumps in the road.
MY two cents.