beam weapons

hey guys... am I missing something or the beam weapons have absolutely no effect on Advent ships...I made the heavy frigates fire beams, an I sent 3 heavy frigates against 1 Radiance Battleship and 1 seeker vessel..2 frigates fired on the capital, and 1 frigate fired on the enemy frigate...and absolutelly no effect..their shields did not come down at all ...nothing, as if they were invincible....they destroyed my frigates, and the enemy ships had absolutelly no scratch on them...is that suppose to happen ?  edit: I am TEC.......edit: the same thing with the vasari and with the rebel ships....what's going on..my heavy frigates do absolutely no damage when they fire their beams...