What gear do / should they start with, and advance to? Power armor, etc..

Sisters of battle are the Orders Militant of the Adepta Sororitas, found on page 41 of the IHB.

Starting gear includes: Club or flail or staff, las pistol and charge pack, carapace chest plate and mesh cowl or feral plate, aquila necklace, chaplet Ecclesiasticus (a decotional icon-amulet), vestments (Good Quality Clothing), 4 candles, writing kit, copy of the Rule of the Sororitas, and Ring of Suffrage (counts as a Charm).

The game doesn't specifiy, but I'd generally hand out at least full carapace when they reach the fork in the career and go militant. After that, Light Power Armour and full Power Armour will follow in (comparably) short order.

Adepta Sororitas found in Ascension only wear light power armour and, of course, a bolter.

a friend playing an AS himself who read much (if not all) about AS said a Sisters of Battle Power armour (angelic Pattern) is equal to Space Marine Armour for the protectiong value (as well as being fusion core powered but it shouldn't provide strength boni or smth like this)

is this true? is there any material on angelic pattern power armour? (except for lexicanum)

Sororitas Power Armour

The power armour worn by the Battle Sisters of the Orders Militant is based on the same archaic systems as that worn by the brethren of the Adeptus Astartes. It provides the same degree of armoured protection, yet must forgo the more advanced life-support and strength enhancing abilities used by the Space Marines, as the Sisters of Battle are not implanted with the Black Carapace that allows Astartes to interface fully with their own armor. Despite this, the Sisters of Battle are one of the few Imperial forces outside the Space Marines to be granted the right to wear such formidible armour, and they are trained to deadly effect to utilise its abilities to the full.

- Codex Witchhunters, page 19

jaysonryder said:

A Sister of the Orders Militant, fully outfited for battlefield combat with her Order would usually be equiped with Power Armor, a Bolter and Frag Grenades plus a combat knife and other essential battle field supplies. The same Sister, in the covert service of the Holy Ordos ought to be equiped with whatever her Inquisitor felt was appropriate and necessary for the completion of her assigned duties.

from france

or a flamer they like to light up heretics. for the number yes it s work in the wargame not in dh maybe because they lack the litle black thing that the space marines have.

Sirion said:

Pretty much. While I doubt it would offer exactly the same level of protection (the tabletop game has to deal with a 1-6 scale, wheres DH has more flexibility in this regard), it's specified as the same calibre of marine armour, but since they lack the Black Carapace they would be more restricted in terms of life-support functions, and likely auto-sensing capacity as well.

Again, I don't think it should offer the exact same protection as astartes armour, because it's going to be smaller and probably a little lighter due to their "human" physiques, but it should be **** close. I've just been getting by fine with regular Power Armour (AP8), and handwaving the battery life because of a military backpack.

I'd give "standard" battle sisters a light power armour version of the Ignatus armour from Ascension and celestines, etc Ignatus armour. The longer battery life goes a long way towards making them more suitable for battlefields than commando missions.