Omron Programmable Terminals NT631 Setup Manual page 45

Method for Connection to the Host
Communica- Communica-
tions Type at tions Type at
PT Host
RS-485 RS-232C
RS-485
28
Usable Connection Method
1:1 connection via a convertor unit
PT
Convertor unit
(NT-AL001)
RS-485
(max. 500 m)
1:N connection via a convertor unit
PT Convertor unit
(NT-AL001)
RS-485
(total length 500 m)
Direct 1:1 connection
PT
RS-485 (max. 500 m)
1:N connection
PT
RS-485 (total length 500 m)
• The RS-232C/RS-422A adapter (NT-AL001) requires +5 V, 150 mA at pin
6 of the RS-232C connector. Check the signals of the RS-232C connector
at the host.
• +5 V is not output from serial port B of the NT631/NT631C. When con-
necting an NT-AL001 at serial port B, a separate power supply is required
for the NT-AL001.
• The cable of an NT-AL001 cannot be connected or disconnected while the
power is ON. Always connect or disconnect the cable while the power
supply from the RS-232C cable is OFF (while the host power supply is
OFF).
• NT Link (1:N) connection is possible even when RS-232C is used at the
NT631/NT631C side for communications with the host, but in this case
one NT-AL001 Adapter is required for each NT631/NT631C. In this case,
it is convenient to use serial port A of the NT631/NT631C. +5 V is not out-
put from serial port B.
Usable Communications
Host
link Link
(1:1)
× ×
Host
RS-232C
(max. 2 m)
× ×
Host
RS-232C
(max. 2 m)
× ×
Host
× ×
Host
❍: Connection possible × : Connection not possible
Section 2-1
Details
Method
NT NT Mem-
Link ory
(1:N) link
❍ ×
page 82
❍ ×
page 86
❍ ×
page 118
❍ ×
page 121