Sony MVS -8000X Quick Setup Manual page 51

As you can see, each physical M/E board can be run in either "1 M/E" mode or divided into two or more
logical M/E partitions. For example, below shows a menu where the first and second boards are running
in 1 M/E mode, but the third board which was used exclusively for M/E 2, has now been divided into
two logical M/Es consisting of M/E 2 and M/E 3.
In this mode, P/P and M/E 1 have 8 keyers, but M/E 2 and M/E 3 will have 4 keyers each. It is very likely
the assignment of these resources as already been discussed between Sony, your engineering
management and your facilities switcher operators.
pg. 51