The Tri-Beam Cannon is unavailable in the Vanilla game.
A deadly weapon found on frigates, destroyers and carriers. Faced with the growing difficulty in increasing the lethality of beam weapons, the Paranid developed the Tri-Beam Laser Cannon, which combines three smaller beam weapons into a single larger, deadlier one.
The Tri-Beam Cannon is one of the semi-implemented experimental beam weapons, and has the worst compatibility of the lot: only the Goner Truelight Seeker is compatible, and probably only because it got a mostly blanket compatibility anyway. It has few redeeming features if scripted in, with damage, range and suchlike being quite similar to the Plasma Beam Cannon, though the PBC has vanilla applications in the form of lasertowers, and better non-vanilla prospects than the TBC due to wider compatiblity.
Known Compatible Ships
Available at Known Docks