Manual

Chapter 2 Connection and Installation
2
21
2.3.6 Connecting the N-42 to RS-422A
RS-422 terminal block assignment
Connecting external equipment
■ Connecting N-42 to external unit
Use the same wiring when connecting the N-42 to the N-42.
• Turn ON the terminators (BL-U1/external unit terminal resistance: 100 ).
➮ See P. viii.
• The cable can be extended to within 1.2 km.
■ Connecting KV-L2*
Connecting the unit to RS-422A port 2
■ Connecting the MELSEC-A series
Connecting with AJ71C24,
AJ71C24-S■■,
AJ71UC24,
A0J2-C214-S1,
A1SJ71(U)C24-R4
RS-422
SG SD+ RD+SD– RD–
SD +
SG
N-42
External unit
(N-42)
SD –
RD +
RD –
RD +
SG
RD –
SD +
SD –
Twisted pair cable
Code Description Signal direction
SG Ground —
SD+ Sends data to + terminal. Output
SD- Sends data to - terminal. Output
RD+ Receives data from + terminal. Input
RD- Receives data from - terminal. Input
SD+
SG
BL-U1*
SD–
RD+
RD–
RDB
SG
Link unit
RDA
SDB
SDA
Twisted pair cable
SD+
SG
BL-U1*
SD–
RD+
RD–
RDA
SG
Link unit Twisted pair cable
RDB
SDA
SDB