Eng overcharging tactical to "counteract damage to tactical systems"

I noticed this in the manual. I actually, just found the manual.

Can anyone explain what this means?

Benefits of Overcharging:
 Beam - increases the rate of fire and damage inflicted by all beam weapons
 Torpedo - decreases load and unload time for all torpedo tubes
 Tactical - increases the speed of Science scans, and counteracts damage to tactical systems