The CTP150 device has removable interface modules from the front, but no removable power modules or fan trays.
In CTP150 devices, slot numbering is from right to left, 0 to 1. Any single module must be installed in slot 0, and any single clock connection must come from the port in slot 0.
CTP150 port numbering on the front panel for the serial interface module is bottom left 0, bottom right 1, top left 2, and top right 3.
Port numbering for the T1/E1 interface module is 1, 2, and 3, left to right.