Electrical Installation - Field and Host Port Connections
CIU 888
Part No.: 4417590_Rev13
3 - 8
Installation Manual
$*6
Direct connection can only be made if the CIU 888 and the DTE (CIU
888 or host computer system) are grounded at the same point.
In all other cases, ensure there is at least a proper galvanic isolation at
the DTE side. Galvanic isolation can also be obtained by means of a
modem connection between the CIU 888 and the host computer
system.
FIGURE 3-7
Field RS485 Port Connection Details
CIU 888
(female)
Prot Ground
TXA
TXB
RXA
RXB
Sign. gnd
DTE/DCE
RXA
RXB
TXA
TXB
Sign. gnd
A) Full Duplex Connection
120 E
120E
(female)
Prot Ground
TXA
TXB
RXA
RXB
Sign. gnd
DTE/DCE
RXA
RXB
TXA
TXB
Sign. gnd
B) Half Duplex Connection
TXA
TXB
RXA
RXB
Sign. gnd
RXA
RXB
TXA
TXB
Sign. gnd
C) Half Duplex – Multi-drop connection
120 E
120 E
TXA
TXB
RXA
RXB
Sign. gnd
TXA
TXB
RXA
RXB
Sign. gnd
(1)
(female)
(2)
(female)
(n)
(female)
Signal Name
9 Pins
Protective ground
RXA
RXB
TXA
TXB
Signal ground
Chassis
2
8
3
7
5
Pin layout for 9 pins D-type
connector
120 E
120 E
CIU 888
CIU 888
CIU 888
CIU 888