Mitsubishi Electric MELSEC-Q Series User Manual page 70

5 ASSIGNMENT OF I/O NUMBERS
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(2) Detail mode
(a) In Detail mode, the number of slots is assigned to the individual base units
(main and extension base units) by setting the I/O assignment of PLC
Parameter.
Use this mode to match the number of slots to the one for the AnS-series
base units (8 fixation).
Since one slot is occupied if an empty slot is set for zero points in I/O
assignment, this mode is also used to make the slot without a module and
later unrecognized.
(b) Cautions on setting the number of slots
The number of slots can be set regardless of the number of slots of the
module being used.
However, the number of slots must be set for all the base units in use.
If the number of slot is not set for all the base units, I/O assignment may not
work correctly.
The followings result if the preset number of slots differs from that of the
installed base units.
1) When the designated number of slots is larger than that of the installed
base unit:
Among the designated slots, those after the slots occupied by the
installed base unit will be empty slots.
For example, when 8 slots are designated for a 5-slot base unit, 3 slots
will be empty slots.
Q35B type main base unit
0 1 2 3 4
The number of points for the empty slots is the one designated by PLC
system of PLC Parameter or with I/O assignment. (Default value is 16
points.)
2) When the designated number of slots is smaller than that of the base
unit being used:
The slots other than those designated are disabled.
For example, when 8 slots are designated for a 12-slot base unit, the 4
slots on the right of the base unit are disabled.
(If a module is installed to the disabled slot, an error [SP. UNIT LAY
ERR.] occurs.)
Q312B type main base unit
0 1 2 3 4 5 6 7 8 9 10 11
Module can be installed.
(When eight slots are set)
5 6 7
Three slots are occupied.
When module is installed,
an error occurs.
MELSEC-Q
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