Omron CJ1W-DRM21, Operation Manual

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4-7
4 Remote I/O Master Communications
CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)
4-1 Master Rem
o
te
I/O C
o
m
m
u
n
ication
s
4
4-1-3 Precau
tions on the
Number
of Maste
r Units
Note You can connect only one Master Unit to a network if you specify a COS or cyclic connection
with the use of CX-Integrator. Remote I/O communication errors may occur. In such a case,
therefore, change the system setup so that only one Master Unit is connected to a network.
Precautions Same as previous net-
works. • The communications cycle time
is longer.
Note The communications cycle
time for the network in the
figure above is TA+TB if sec-
tions A and B above are
separate networks with a
communications cycle time
of TA and TB.
• Multiple Master Units cannot
share a single Slave Unit.
• Bus Off errors (communica-
tions stopped by multiple trans-
missions) may occur if multiple
Master Units with disabled scan
lists are present on a single net-
work.
• Make sure that each word allo-
cated in the system is allocated
to only one Master Unit.
Pattern One Master Unit con-
nected on a single net-
work
Multiple Master Units con-
nected on a single network
Multiple Master Units con-
nected to a single CPU Unit