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Saia-Burgess Controls AG
Manual PCD7.D412DTPF & PCD7.D4xxxT5F │ Document 27-620 – Release ENG07 │ 2019-06-20
3-9
Logic Controller
Communications interfaces
3
3.1.2.3
PCD7.F150S Serial Interface Module RS-485 with Electrical Isolation
Electrical isolation is achieved with three optocouplers and a DC/DC converter.
Data signals are protected against overvoltage with an anti-surge diode (10 V).
Electrical isolation is achieved using three optical couplers and a DC/DC converter.
The data signals are protected against excess voltages by a suppressor diode
(10 V).
The line terminator for port x.1 is integrated into the module and can be activated
using the silde switch on the module.
PCD7.F150S
RS-485 terminator
Slider
1 2
ON
C
O
Closed terminated
Slider
1 2
ON
C
O
Open not terminated
(factory setting)
RS 485 connection -
10 pin spring-loaded terminal block
Port x.1
RS-485
PGND
PGND
RX - TX
/RX - /TX
x0
x1
x2
RX - TX
/RX - /TX
GND
RS-485
RS-485
RS-485
Peripherie-
device
PCD Modul
Terminal
0 PGND
Rx-Tx
1
2
/Rx-/Tx
3
4
PGND 5
6
7
8
(SGD)
9
When using this module, the permitted ambient temperature for the control unit is
reduced by 5°C.
Line terminator:
+5 V
/RX - /TX
n
n
29
n
/n
/n
/n
28
RX - TX
+5 V
Pull up
330 Ohm
Termination
Resistor
150 Ohm
Segment length max. 1200 m
max. 32 stations
Bus RS-485
First station
Middle stations
End station
Pull down
330 Ohm
More details are available in the manual 26-740 “Installation components for
RS-485 networks”.