Power transformer connection symbol ...+syn0

[jkristinn]

I'm trying to figure out what the "s" in the connection symbol YNd11+syn0 stands for. The +syn0 is a low power auxiliary winding. The rating plate is in english (as far as I understand) so "service" is my best guess, but I would appreciate it if someone could correct me or confirm my guess.

 

[jkristinn]

I have received the answer. The "s" stands for "sparkopplad" which means auto transformer in Swedish.