You can claim a drawn game in accordance with the 50 move rule. I tried to verify this in the site FAQ but for me that isn't currently working, but I do believe this rule is applicable here at RHP.
Also remember that it isn't automatic. You would have to claim the draw when you feel that it applies to your game. If you're not sure, just go ahead and make the claim. If the conditions have not been met, nothing will happen and the game will go on. But you have to make the claim.
"The fifty-move rule in chess states that a player can claim a draw if no capture has been made and no pawn has been moved in the last fifty moves (for this purpose a "move" consists of a player completing his turn followed by his opponent completing his turn). The purpose of this rule is to prevent a player with no chance of winning from obstinately continuing to play indefinitely (Hooper & Whyld 1992:134), or seeking to win purely by tiring the opponent out."