If I hover over the icon for Feedback Pulse it only says "Reflects energy weapons back to the target for 15 sec". Is there any way I can see what effect it has when I add appropriate consoles or skillpoints for this ability or change aux power level?
In space, try opening the powers menu (press 'P'). Scroll down and click on Feed Back Pulse. If it works like some of the other offensive skills it there should be a bunch of useful information on the right. I just don't have it to check and be sure.
Thats because the strengt of the Feedbackpulse depends on the damage that is activating it. So lets say you activate your FBP and im Hitting you with a 10k Damage attack ...then ,as far as i remember, FBP 1gives 33% - 3333 Damage ,FBP 2 66% 6666 Damage and FBP 3 100% 10000 Damage back for this one Attack. I dont know if this numbers are still right since ive not used it since the downgrade after the initial release.
You don't check it, other than parsing or looking through your combat logs. The values aren't listed anywhere in game, for some reason.
FBP is 33/66/100% damage return (split 50/50 between shields and hull), under ideal conditions. Meaning high Aux and heavy spec'ing.
Also, the 33/66/100% per rank is an asymptote; you'll never quite reach those values (though you'll get very close) and there are severe diminishing returns.
That being said, FBP greatly benefits from resistance debuffs upon your target. From Open Beta up until about 2 months ago, I used an FBP 3 build on my Sci. Tank in with TacTeam + EPtS, fire off Sensor Scan + AP: Delta and then watch people melt under FBP. It's amazing to see Escorts nuke themselves on their Alphas.