Mitsubishi Electric AJ71C24-S6 User Manual page 72

4.
SElTINGS AND PROCEDURES BEFORE OPERATION
MELSEC-A
4.5
External Wiring
4.5.1
Precautions during wiring
External wirin
reliable AJ71(
g which is resistant t o external noise effects is a pre
>24 operations (full use of all available functions).
for
When doing external wiring of the AJ71C24, the following precautions must
be taken:
(1)
Keep main circuit wiring, high-voltage wiring, and other load-carrying
wiring outside the PC CPU separate from AJ71C24 wiring. Never bundle
them together. This prevents noise and surge-induction effects.
(2)
Ground the shield of shielded wires and cables at only one point
(3) The RS-422 terminal has M4 screw connectors. Fasten suitably-sized
crimped terminals t o the ends of the cables before connecting the cables
t o the terminals.
4.5.2 Connecting the RS-232C connectors
Precautions and examples of connections to an RS-232C connector is shown
i n the diagram below.
(1) Precautions during connections
(a) If the FG and SG terminals are connected inside a device connected
to the RS-232C connector, do not use terminal No. 1 of the RS-232C
connector of the AJ71C24.
(b) If half-duplex transmission (see Section 7.2 for the setting method)
is used, perform wiring so that the CD signal of the AJ71C24 can be
controlled by the external device.
Also, set the AJ71C24 t o execute the CD terminal check (see Section
7.1).
I
Section 5.4 gives the ONIOFF timing control of the CD signal of the
AJ71C24 using the external device.