I have researched up to Epsilon . Regen rate 3. How does strength size work? say size 55 , Does it mean 55 hit points then collapses
That is correct. The design will also tell you how many seconds it will take for it to regenerate completely, provided the shield generator is still intact.
Shields are especially useful in the following situations:
- In protracted battles and/or when you take some damage, then there's a pause before you take some more. The shield will have time to regenerate between battles/between damage taken. Keep in mind, armor can only be repaired at a shipyard instead
- Against armor piercing weapons (particle beams and especially lances), weapons that ignore armor (Microwave) or weapons that do a lot of damage in a single hit, say a spinal laser. This is because a particularly powerful hit can pierce all your layers of armor, while shields will protect until they are depleted no matter how strong a single hit is.
- For the reason above, a ship that only relays on armor may, due to unlucky hits, have some places where the armor is completely stripped off. While this page is for vb aurora, it can still help
http://aurorawiki.pentarch.org/index.php?title=Armor. A shield can complement your armor to avoid a situation like that
In general, in my opinion, it is worth to put shields on any "general purpose" warship of a certain size if you have the tech to make decent shields (basically means, if you kept up your shield research to a comparable level to your armor research).
Shields do not perform well againt massed concentrated damage. Say, a hundred missiles that hit you all at once. In those situations using just armor is better, however if it's normal for you to take massive amounts of damage, you probably have other problems anyway xD
Also, meson cannons will ignore shields