Newbie question on ammunition.. ?

[Gruden]

Just tried the demo out recently and have been playing around a bit with it. I noticed that some weapons I use I seem to be able to fire once and beyond that they are useless for the remainder of that battle. Others I seem to be able to fire every round. How can you determine which weapons have a limited number of times they can fire? One such weapon is one I found in ruins. I think it was like an Ionic Engine destroyer or something, takes up 100kt of space. It never seems to recharge.

I know that in some other games I've played like this (MOOII), certain weapons needed time to re-energize before firing again. Is this the case in SEIV? I noticed missles also seem to have a delay...

Any help for the newcomer? Thanks in advance!