Mitsubishi Electronics FX0N-485ADP, FX-485ADP manual Examples of one-pair wiring for RS-485 circuit

2.2Examples of one-pair wiring (for RS-485 circuit)

(1)When connecting one computer and one PC

485PC-IF	Cable connection and signal direction	485ADP	Application
Signal name		Signal name

SDA		RDA	Reception data
SDB		R*1	Reception data
		RDB
RDA		SDA	Transmission data
R*1		SDB	Transmission data
RDB
LINK SG		LINK SG	Signal ground
Grounding		FG *2	Frame ground
		24V *3	Power supply terminal
resistance of	DC24V
100 Ω or less	FX base unit	24G *3	Power supply terminal

(2)Computer and PCs in 1 : n connection ( n has a maximum value of 16 ).

The terminal lagout shown is diagrammatic only. As for 485ADP, see chapter 1, and as for 485PC-IF, and computer link unit for A series PC, see the individual manuals.

Computer

SD

RD

485PC-IF		485ADP
		Station
		No. 0
	SDA	SDA
SD	SDB	SDB
R*1	RDA	RDA
RD	RDB	RDB
	LINK	LINK
	SG	SG
		*2
		FG

485ADP	485ADP
Station	Station
No. 1	No. 15
SDA	SDA
SDB	SDB
RDA	RDA	*1
		R
RDB	RDB
LINK	LINK
SG	SG
*2	*2
FG	FG

*1 R is the terminating resistance. Connect the terminating resistance (110 Ω) between terminals

RDA and RDB . For details see section 2.3.

*2 Connect terminal FG to earth terminal of the PC main body grounded with resistance of 100

Ωor less. However, as for the computer link unit of the A series PC, see the manual of the computer link unit.

*3 The 24V DC power requirement can be taker from the service power supply of the PC.