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25
Connecting Link Adapters and RS-422A Converters
Section 2-3
Note
The hood will have the same electrical potential as the connector on the other
end of the cable.
RS-422A/485 Terminal
Block
Block Diagram
DIP Switch Settings
Note
(1) Set pins 2 and 3 to the same setting. (ON for the two-wire method or OFF
for the four-wire method.)
(2) To prohibit echoback, set pin 5 to ON (with RS control).
Signal
RDA–
RDB+
SDA–
SDB+
FG
SD
RS
CS
RD
ER
DR
SV
SG
FG
SW.6
SW.5
SW.2
SW.3
SW.1
SDB(+)
SDA( -)
RDB(+)
RDA(-)
FG
Pin
number
Function
ON
OFF
1
Terminating resistance
With (at both ends of the commu-
nications path)
Without
2
Two-wire/four-wire method selec-
tion (See note 1.)
Two-wire method
Four-wire method
3
Two-wire/four-wire method selec-
tion (See note 1.)
Two-wire method
Four-wire method
4
Not used.
---
---
5
Selection of RS control for RD
(See note 2.)
With RS control
Without RS control (always ready
to receive)
6
Selection of RS control for SD
(See note 3.)
With RS control
Without RS control (always ready
to send)
Summary of Contents for NT20
Page 1: ...Programmable Terminal Cat No V091 E1 01 NT20 USER S MANUAL ...
Page 2: ...NT series Programmable Terminal User s Manual Produced March 2007 ...
Page 3: ...iv ...
Page 5: ...vi ...
Page 9: ...x TABLE OF CONTENTS ...
Page 15: ...xvi ...
Page 21: ...xxii EC Directives 6 ...
Page 37: ...16 Before Operating Section 1 6 ...
Page 153: ...132 Transferring the Resource Data Section 3 11 ...
Page 185: ...164 Numeral Setting Section 4 8 ...
Page 267: ...246 Key to Programs Section 6 8 ...
Page 281: ...260 Specifications Appendix A ...
Page 285: ...264 Transporting and Storing PTs Appendix C ...
Page 303: ...282 Function Restrictions Depending on the Support Tool Appendix I ...
Page 307: ...286 Index ...
Page 309: ...288 Revision History ...