HK-Aerial Mark 7 and Mark 8 were equipped with plasma cannons.
NOW Comics timeline
The Habitat had developed mobile charge plasma cannons with 10 times the range of normal plasma assault rifles.
2029 and Rampage timeline
In order to destroy the Meta-Node in 1988, a Resistance commando had to gather parts in Cyberdyne Systems Laboratory to complete the V-TEC Phased Plasma Cannon, which he would used to terminate the Meta-Node successfully.
Rise of the Machines timeline
The plasma cannon was one of Model T-X's onboard weaponry.
In 2031, the T-X Terminatrix was engaging a T-800 Infiltrator and a T-1002 in Skynet main facility. she used plasma cannon to destroy the T-1002. The T-X then dodged attacked from the T-800 and fired IAD-ChemTech against it. After the plasma cannon was recharged, the T-X used it to destroy the T-800.
During her mission in 2004 (2003), the T-X had used plasma cannon for various times. The T-850 sent by the Resistance was once hit by plasma cannon, which damaged one of its hydrogen fuel cell. However, the T-850 was managed to destroyed the T-X's plasma cannon with RPG when she attempted to kill Kate Brewster. T-X later switched its default weapon into IAD-ChemTech in Rise of the Machines timeline. While in Kyla's World, the T-X studied the damage for a few milliseconds before her diagnostic-repair processor immediately devised a solution. With her free hand, she twisted and bent the various plasma magnetic containment conduits into a new, much smaller, cruder transmission head. Only a fraction of her available power could be transmitted with the new arrangement, but the repaired weapon would still be formidable.