User`s manual

Basics Features of the MELSEC System Q
2 – 2
Base units
The Q00JCPU and Q00UJCPU include power supply, CPU and main base unit with five slots.
All other CPUs have to be mounted on a main base unit. Additionally one or two power supplies
can be mounted and up to twelve modules.
Extension base units can be connected to the main base unit via bus cable. The extension base
units are available with or without slots for a separate power supply and with slots for up to twelve
modules.
The Q00JCPU and Q00UJCPU can adress max. 16 modules on one main base unit and two
extension base units.
The CPU modules Q00CPU, Q01CPU, Q00UCPU, Q01UCPU and Q02UCPU are extendable
with up to four extension base units and totally 24 modules (36 modules with Q02UCPU).
Except for Q12PRHCPU and Q25PRHCPU, all other CPU types can be extended with seven
extension base units with maximum 64 slots total. The maximum distance between main base
unit and last extension base unit is 13.2 m, so that the base units can be mounted inside the cab-
inet with some distance between each other.
● Connecting extension base units to a redundant PLC system
It is not possible to connect an extension base unit to a main base unit with a redundant
CPU up to serial no. 09012... The expansion can be done by remote I/O station via
MELSECNET/H network.
It is possible to connect a main base unit with a redundant Q12PRHCPU or Q25PRHCPU
beginning at serial no. 09012… up to maximum seven extension base units with totally
63 modules.
The first extension base unit must be the type Q65WRB, the second to seventh unit can be
of type Q68RB.
Up to 8192 inputs and outputs
The CPU types Q02(H) to Q25H, the universal model CPUs from Q03UD(E)CPU on, all process
CPUs and redundant CPUs can address up to 4096 in/outputs directly on the base unit.
Together with remote I/Os these CPUs can address up to 8192 I/O points.
A Q02UCPU can address up to 2048 in/outputs directly and up to 8192 I/Os totally.
The Q00JCPU and Q00UJCPU address 256 I/O points directly. The Q00CPU, Q00UCPU,
Q01CPU or Q01UCPU addresses 1024 I/O points. With these CPU types the number is
extended to 2048 points and to 8192 points with the universal model PLC CPUs by remote I/Os.