Mitsubishi MELSEC-A Series Reference Manual page 76

4. COMPOSITION OF A THREE-TIER SYSTEM
4.4.2 Precautions when using data link
This section explains precautions for configuring a three-tier system.
(1)
(2)
Setting link parameters
In the three-tier system, setting link parameters to CPU modules for the master
stations in the second and third tiers is required.
For link parameter setting, refer to Section 5.3.7 and Chapter 7.
Restriction on use of link modules
Up to two of the following link modules (one as a master station and the other as a
local station) can be used with a CPU module.
(The two modules cannot be used only for master stations or local stations.)
AJ71AT21B
A1SJ71AT21B
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