Mitsubishi FX3U-485-BD User Manual

D-29
FX Series PLC User's Manual - Data Communication Edition
Computer Link
4 Wiring
4.2 Selecting Connection Method
A
Common Items
B
N:N Network
C
Parallel Link
D
Computer Link
E
Inverter Communication
F
Non-Protocol Communication (RS/RS2 Instruction)
G
Non-Protocol Communication (FX
2N
-232IF)
H
Programming Communication
I
Remote Maintenance
Apx.
Discontinued models
4.2 Selecting Connection Method
When using computer link, communication can be achieved in accordance with RS-232C or RS-485 (422).
In FX
3G, FX3U and FX3UC PLCs, computer link is applicable in up to two channels at the same time. In such a
case, communication can be achieved in accordance with RS-232C on both channels, in accordance with
RS-485 on both channels, or in accordance with RS-232C on one channel and RS-485 on the other channel.
4.2.1 For communication in accordance with RS-232C (1-to-1 connection)
With communication in accordance with RS-232C, 1-to-1 connection is applicable. Make sure that the total
extension distance is 15 m (49' 2") or less.
4.2.2 For communication in accordance with RS-485 (RS-422) (1-to-N connection)
With communication in accordance with RS-485 (RS-422), up to 16 PLCs can be connected. Make sure that
the total extension distance is 500 m (1640' 5") or less [50 m (164' 0") or less when 485BD is included].
One-pair wiring and two-pair wiring are applicable for communication in accordance with RS-485 (RS-422).
The wiring method is determined for each application. Refer to the table below, and perform suitable wiring.
: Recommended wiring method, : Applicable wiring method, —: Non-applicable wiring method
*1. When computer link is added to an existing system, adopt the wiring method used in the existing
system.
*2. For the message waiting time, refer to Subsection 6.4.3.
*3. "Echo transfer" is generated when the FX-485PC-IF is used in the one-pair wiring.
Take proper countermeasures in the computer so that the echo transfer can be ignored.
One-pair
wiring
Two-pair
wiring
Computer link
*1
When the message waiting time
*2
should be 70 ms or less
— 
When the message waiting time
*2
may be more than 70 ms 
*3

When the on-demand function is used — 
Communication equipment operating
in accordance with RS-232C
Personal computer FX PLC
15 m (49' 2") or less
+
FX-485PC-IF
Communication equipment
operating in accordance
with RS-485
Communication equipment
operating in accordance
with RS-485
Personal computer FX PLC
Station No. 0
Station No. 15
++
. . .
RS-232C/RS-485
communication
converter
FX PLC

Mitsubishi FX3U-485-BD Specifications

General

Brand	Mitsubishi
Model	FX3U-485-BD
Category	Controller
Language	English