19
System Configuration Section 1-2
Note 1. An Analog Power Supply Unit is counted as one Unit, the same as I/O Units
and Dedicated I/O Units.
2. I/O points = Input points (256 max.) + Output points (256 max.)
Exceeding the Maximum
Number of I/O Units
When only a CPU Block is used, a maximum of 11 I/O Units and Dedicated I/
O Units can be connected to the CQM1H-series CPU Unit. When an Expan-
sion I/O Block is also used, a maximum of 5 I/O Units and Dedicated I/O Units
can be connected to the CQM1H-series CPU Unit and a maximum of 11 I/O
Units and Dedicated I/O Units can be connected to the Expansion I/O Block. If
these limits are exceeded, the CQM1H may not operate properly because of
drops in the voltage of the 5-V internal power supply. The CQM1H will detect if
the maximum number of I/O points has been exceeded (as explained below),
but will not detect if the maximum number of Units has been exceeded. There-
fore, design the system so that the maximum number of Units is not
exceeded.
Exceeding Maximum
Number of I/O Points
When the maximum number of I/O points is exceeded, an “I/O UNIT OVER”
message will be displayed and operation will stop. For details on I/O UNIT
OVER errors, refer to the CQM1H Programming Manual.
The relationship between the maximum number of I/O points and Unit word
allocation is shown in the following table. The CPU Unit has 16 built-in inputs
for which one word is allocated.
Power Supply Unit
CPU Unit (16 inputs built in)
I/O Control Unit
Two Inner Board slots
Up to five Units con-
nectable as required
Up to eleven Units con-
nectable as required
I/O Interface Unit
Communications Unit
CPU Unit
I/O Units or
Dedicated
I/O Units
Expansion I/O Cable
End cover
End Cover
CPU Unit Max. no. of I/O
points
Input allocation Output
allocation
Requirements
CPU Unit Connected Units Connected Units
CQM1H-CPU61 512 (32 words) 1 word n words m words 1 + n + m ≤ 32
(n, m ≤ 16)
CQM1H-CPU51
CQM1H-CPU21 256 (16 words) 1 word n words m words 1 + n + m ≤ 16
(n, m ≤ 16)
CQM1H-CPU11
To Next Page
Loading...
