144 Device MountingModular VTO consists of single module mounting, double module mounting and 3-modulemounting. Take 3-module mounting for example. When leaving factory by default, visiting cards and card cover have been included in theattachment. When power-on after mounting, please ensure that all modules have been connected;otherwise, they fail to work normally. Before installation of surface mounting box and flush mounting box, cables in the wall shallgo through the bracket or flush mounting box.4.1 Surface MountingDrill holes according to hole positions of surface mounting box, and put expansion pipeStep 1in place.Fix surface mounting box onto the wall with ST3×18 screws.Step 2Fix every module onto front panel with M3×6 screws.Step 3Connect cables. Please refer to “2 Product Structure”.Step 4Fix the front panel onto surface mounting box with M4×40 screws.Step 5Apply glue between surface mounting box and the wall.Step 6Write room number or the user’s name on the visiting card, and insert it into userStep 7directory.