4 SETTINGS AND PROCEDURES PRIOR TO OPERATION

4.4 External Wiring

MELSEC-Q

This section explains wiring between the Q series C24 and external device.

As the wiring precautions, external wiring which is resistant to the effects of external noise is a prerequisite for reliable system operation and full use of the Q series C24 function.

(1)Ground the shield at only one point.

(2)When connecting with an external device using an RS-232 line, use a connector shell as specified in Section 3.2.1 on the Q series C24 end.

(3)When connecting with an external device using an RS-422/485 cable, be sure to note the following.

(a)QJ71C24N and QJ71C24

1)Use the RS-422/485 cable recommended in section 3.3.2.

2)The RS-422/485 interface terminal block uses M3 terminal screws. Use suitable crimp-on terminals for the terminals.

(b)QJ71C24N-R4

1)Use the RS-422/485 cable recommended in section 3.3.2.

Be sure to strip the outer insulation layer by 7 mm before connecting the cable to the plug-in socket block.

2)When connecting the braided shield wire inside the RS-422/485 cable, use the plate terminals included with the product. The braided shield wire can be connected without the plate terminal. Four plate terminals are included to connect the FG terminals of both stations. (see section 4.4.2.(6).)

3)When connecting the plug-in socket block to the QJ71C24N-R4, be sure to confirm the layout of the socket block, and then insert it into the RS-422/485 connector on the QJ71C24N-R4.

QJ71C24N-R4

 

 

 

 

 

 

RUN

ERR.

 

 

 

 

 

NEU.

NEU.

 

 

 

 

 

CH1 SD

SD

CH2

 

 

 

 

 

 

RD

RD

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SDA

 

 

 

 

 

 

CH1

 

 

 

 

 

 

 

 

 

RS-422/485

 

 

 

 

 

SDB

 

 

 

 

 

SDA

 

 

 

 

 

 

 

 

 

 

SDB

 

 

 

 

 

RDA

 

 

 

 

 

RDA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RDB

 

 

 

 

 

RDB

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SG

 

 

 

 

 

SG

 

 

 

 

(FG)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CH2

 

 

 

 

 

(FG)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RS-422/485

 

 

 

 

 

 

 

 

 

 

 

SDA

 

 

 

 

 

 

 

 

 

 

 

SDB

 

 

 

 

 

 

 

 

 

 

 

RDA

 

 

 

 

 

 

 

 

 

 

 

RDB

 

 

 

 

 

 

 

 

 

 

 

SG

 

 

 

 

 

 

 

 

 

 

(FG)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

7

 

mm

(0.

in.

 

 

)

Braided shield wire

Plate terminal (included with product)

QJ71C24N-R4

(4)Connect the external device according to its specifications.

(5)See Appendix 5 for the bend radius of the connection cable.

4 - 5

4 - 5