When can you use there action

Whenever there is an action window where you get to activate and fulfil the criteria (i.e. units at the planet in question, PBs are unexhausted) .

See page 20-22: http://www.fantasyflightgames.com/ffg_content/warhammer-40k-conquest/support/Rules-Reference-web.pdf

so basicaly any phase you can use an action ie deploy and combat

Where the requirements are met, yes.

Got a quick question, A battle action is that the text on the planet cards.

Got a quick question, A battle action is that the text on the planet cards.

Yes. The ones that start with the word "Battle" that can be triggered by the winner of a battle at that planet.

^{there is an eldar card that says it stops the effects of battle actions, so its talking about the planet cards}

^{there is an eldar card that says it stops the effects of battle actions, so its talking about the planet cards}

Yes. Don't confuse actions that start with "Battle" (found only on planet cards) with actions that start with "Combat" (found on just about any card type other than planets). The two words do not mean the same thing in this game.

ok thank you for your help, had a bit of an argument with my brother over this, he got confused when he saw battle he thoughtn it meant the actions in the combat phase and tryed to stop some damage from my warp storm being a combat action. thaks for the help again and the claification.

Your brother isn't alone. A lot of people have thought that "battle" and "combat" are interchangeable when reading that card. It's an easy mistake to make since there are never more than 7 battle abilities in a game.

i can see how it would have been easy to get cofused i was as well for a time.