I was explaining the difference between dual heavies and normals to my fleet (weapon rotations and the shared cooldown when 3 are equipped), and suddenly got puzzled when comparing the damage to dps listed ingame for Dual Cannons. After searching the two wikis and a few pages of a search on this forum, couldn't find information about this exact topic.
As an example, Mk III of the weapon states it deals 172 dps, and 129 damage per cycle.
It was my understanding (and from ingame testing) the weapon fires once per 2 seconds.
129 damage / 2 seconds = 64.5 damage/second.
I then thought, perhaps the numbers are weird and list per shot rather than per cycle.
This is based off the information of all the same damage type weapons with right click weapon information for toggle duration and reuse time.
Beams fire 1 beam of damage every second and fires for 4 seconds and recharges in 1 second.
Cannons fire 2 shots of damage a second with Turrets and Non Heavy cannons firing for 2 seconds with a 1 second recharge, while Heavy Cannon fires 1 second with a 2 second cooldown
% of Single Beam damage over time(approximate)
Single Beam 100%
Single Cannon 120%
Dual Beam 133%
Dual Cannon 166%
Dual Heavy Cannon 166%
A dual cannon will fire 4 shots in 2 seconds then have to wait 1 second for a 3 second cycle so in your case. (damage x 4) divided by 3 = dps
All cannons take 3 seconds to complete their cycle time.
Heavy cannons fire 2 shots over 1 second, then cooldown for 2 seconds - total 3 seconds
Dual cannons fire 4 shots over 2 seconds, then cooldown for 1 second - total 3 seconds.
from your example of dual cannons:
Mk III of the weapon states it deals 172 dps, and 129 damage per cycle.
129 x 4 = 516 damage done. divided by 3 seconds = 172 dps
Cannons can be a little misleading because of the sustaining factor. You can only chain 2 dual cannons together (continuously) due to the firing cycle time of 2 seconds (1 second CD). With MK3 the best you can sustain is therefore, 258 DPS. However the best you can sustain with heavies is 3 cannons (1 second firing cycle, 2 second CD) which actually means they can chain/sustain twice what dual cannons can because of the shorter firing cycle (still 2 shots per second). Of course at the cost of an additional hardpoint...