Tran,
I had the 211AE and could not find the main fuse. I called CARY. Unplug the power cords IEC connector from the amp. The fuse holder is directly beneath and can only be accessed with the IEC connector unpluged from the amp. At the bottom of the IEC inlet / receptacle is the fuse holder. You should see a small space in the center at the bottom of the inlet. I used a small screw driver in that space to pull out the fuse holder. I found that there was a spare fuse in the holder, if you don't have one on hand. Enjoy! Bill