Toshiba VF-A7 instruction manual Serial RS485 communication connector

2.3.3 Serial RS485 communication connector

■Figure of serial RS485 communication connector To use the serial RS485 connector, detach the cover for serial RS485 connector.

Pin-8 Pin-1

	Signal name		Pin number			content
	RXA		4	Same phase reception data(positive line)
	RXB		5	Anti-phase reception data(positive line)
	TXA		3	Same phase transmitting data(positive line)
	TXB		6	Anti-phase transmitting data(positive line)
	SG		2,8	Ground line of signal data
This table shows signal line of inverter side.
(Example: RXA signal is received by inverter.)
※Never use pin-1(24Vdc) and pin-7(5Vdc).
■Connecting diagrams for RS485 communication
	Upper computer			cross each other			straight
				VF-A7(slave)			VF-A7(slave)
	or VF-A7(master)
	RXA				RXA			RXA
	RXB				RXB			RXB
	TXA				TXA			TXA
	TXB				TXB			TXB
		SG			SG			SG

straight

VF-A7(slave)

RXA

RXB

TXA

TXB

SG

Terminal resistor 100Ω-1/4W

■Note

※Detach a communication line and the main circuit wiring 20cm or more.

※Do not connect pin-1(24Vdc) and pin-7(5Vdc).

※Twist the lines between RXA and RXB, between TXA and TXB by the twist pair cable.

※Connect terminus resistance at the terminal (both ends) of a transmission way.

※When you use it by 2 line type, please short-circuit between RXB and TXB, between RXA and TXA.

※Master side reception(pin-4,pin-5) / slave side transmitting(pin-3,pin-6) lines may not connect at the time of communication between inverters.

※Fix the communication cable, and do not apply the stress to the RS485 connector.

B-11