The Nos. of cabinets start from 0. Frames are numbered according to their locations in a cabinet, from bottom to top.  Each cabinet can hold three frames at most. The frames in a cabinet are usually placed and numbered from bottom to top. If there is only one frame in a cabinet, the frame shall be placed in the middle of the cabinet for the convenience of monitoring the power distribution system. The main control frame is manages and maintains the whole UMG8900 while providing services. It is configured by default and always numbered 1. It cannot be added or deleted.

N.B.

If the networking requires an independent central switching frame, its frame No. is 0.

The control frame is needed only for large capacity configuration. Its frame No. is 8.

FIGURE: Frame configuration related commands.

discussed well. 

important topic

useful document, thanks