When is a 7-candle menorah lit today?

It's not. The menorah is the seven-branched candelabrum that stood in the Temple in antiquity; since the destruction of the Temple, menorot aren't lighted ritually. The nine-branched candelabrum we light at Chanukah is more properly called a 'chanukiah'. read more

A 7 branch menorah is never lit. The seven-branched menorah is the oldest symbol of the Jewish religion. The original menorah stood in the First and Second Temples in Jerusalem. The priests would light it in the sanctuary each day. According to the Talmud it is forbidden to use a seven-branched menorah outside of the Temple. read more

We place candles in the Menorah from right to left, but we light the candles from left to right. On the first night we light one candle on the right side. On the second night we light the new, candle first, starting from the left and moving to the right. read more