Figure 4-12 When The Primary Ring And Secondary Ring Are Disconnected At - Hitachi S10mini OD.RING Hardware Manual

4 USER GUIDE
If the primary ring and secondary ring are disconnected at different places (between different
modules), normal communication is impossible. (Depending on the number of modules
connected, CPL Nos., and number of words transferred, some modules may be unable to transfer
data at all. Some modules may also be unable to transfer data intermittently.)
Figure 4-12 When the Primary Ring and Secondary Ring are Disconnected at Different
Places
As shown in Figure 4-12, if the primary ring and secondary ring are disconnected
at different places (between different modules), normal communication may be
impossible. In these cases, be sure not to use the modules.
All the modules should also be programmed so that they can detect an error and
issue an alarm when the primary ring or secondary ring is disconnected at one
place.
Example: When the CPL No. of the connected OD.RING module is from 0 to 5
and the starting address of the RAS table is set to RWF00. (The
figure below shows the case where YF70 is assigned to the coil for
alarm issuance.)
A
Primary ring
F
Secondary ring
RF00
RF05
RF40
RF45
B C
E D
A through D are OD.RING modules.
CAUTION
YF70
4-10