Mitsubishi Electric MELSEC-Q00U(J)CPU User Manual page 55

(b) Setting the number of slots smaller than the actual one
Set the smaller number than the actual number of slots when slots with no module mounted need not be
recognized.
Four slots from the right end of the base unit will be the prohibited slots when using a 12-slot base unit
Ex.
and setting the number of available slots to eight. (Mounting a module on a prohibited slot causes
"SP.UNIT LAY ERR.".)
Main base unit
Q312B
Power supply
module
CPU module
CPU 0 1 2 3 4 5
Number of slots set
CHAPTER 2 APPLICATION OF PROGRAMMING
Actual number of slots
6 7 8 9 10 11 Slot number
Mounting a module will result in an error.
2
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