Glenmac,
My battery has 500 cca(cold cranking amps) I am not sure what the reserve cca are,I need a bigger battery and a little bigger alternator,but I get buy with what I have.
It will drain your battery while the motor is running(faster than the tractor can return the amps to the battery),if it is a hard enough and long enough pull,somethings pull easier than others,like a big log does not pull as easy as a stuck tractor where the wheels turn and with the engine running you can help yourself along while the winch is pulling. It is something you just have to get used to,most places when you have your tractor stuck 10' pull at the most usually and you should be out of the hole no problem,but if you pull 100' of cable out and try to pull your self up a cliff unassisted and the winch doing all of the work,you are going to have stop occasionally and let the battery charge back up. On along pull the winch is going to drain more amps than the tractor can recover,but a short pull I get myself out of the fix,run the cable back on the winch and keep on driving. The 1st time I used the winch,the instructions recommend you unwind all the cable and stretch the cable a little when new,which I did and I let the winch pull the tractor while it was idling up an incline,after a while I stalled it somehow,and I had to get the pickup and jumper cables.
If you want to ask me anything else let me know and I will try to help,all I can say is this thing has helped out of some real jams deep in the woods.Also if I cut a tree down and it falls into another (which with my luck happens on occasion) I can drag the tree down on the ground or out of the multiflora rose etc.