Mitsubishi Electric MELSEC-A User Manual page 105

13. SElTINGS AND PROCEDURES BEFORE OPERATION
MELSEC-A
13.3.4 Connection of terminal resistance
Connect terminal resistance to the stations at both ends of a system con-
nected by cable.
An example of a connecting terminal resistance is given below.
(1) Modules to which a terminal resistance needs to be connected
(a) When the following module is used as a master station:
AJ71 UC24 :
RS-422 communication (terminal resistance:
330 R) or RS-485 (terminal resistance: 110
Q)
AOJ2-C214(S1)
:
RS-422 communication (terminal resistance: 330 R)
AJ71C22(SI) : RS-422 communication (terminal resistance: 330 0 )
Master Local Local Local Local
0:
Connect terminal resistance to the shaded modules.
(b) When the following module is used as a local station:
AJ71 UG24
: RS-422 communication (terminal resistance:
330 R ) or RS-485 (terminal resistance: 110
n)
AOJ2-C214(SI) : RS-422 communication (terminal resistance: 330 R)
AOJ2C25 : RS-422 communication (terminal resistance: 330 R)
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. . ... .
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. . . .
. . .
. . . . . .
-
. . . .
.. . . .
...
. . . . . . .
. .
Master
-----
Local Local
-
. . . . . .
. .
. . . . . .
. . . . .
-
n
Remote Local
r-7
Terminal re- Without re- Without re- Without re- Terminal re-
sistance is sistance sistance sistance sistance is
necessary necessary
Terminal re-
sistance is
necessary
Without re- Without re- Without re- Terminal re-
sistance sistance sistance sistance is
necessary
0:
Connect terminal resistance to the shaded modules.