In Hebrew Qabalah? You mean Hebrew gematria, right... ?
As said above - 30 traditionally refers Lamed. This letter is referred to Libra in astrology & Adjustment in the Tarot.
"the Sun" is card 19, attributed to Resh (value of 200). where did you get the idea that its equal to teh Sun?
Other words that are 30 in Hebrew gematria: ChIIB = "A party to an action at law; defendent; plaintiff [Note: Lamed = 30 = Libra = 'Justice']". Also: YHVDH = "Judah" and IHIH which means "It will be"