Hardware manual PCD7.LRxx-PG5 room controller │ Document 27-653; version ENG07 │ 2019-03-21
Saia-Burgess Controls AG
Communication
5
5-5
RS-485 interfaces (ports 0 + 1) in general
AO0…
GND
0-10V
V
UI0…
0-10V
GND
Dig.
NTC
V
RS485 / Port 0
/D A +
D B -
RO3 IN3 RN RN IN0 RO0 IN1 RO1 IN2 RO2
TN T~ TO0 TN TO1
RUN/HALT
Power Supply
---
230 V In
24 VAC In
24 VAC Out
Sylk Bus
RS485 / Port 1
USB
T1 R1 T0 R0 !
1
L
2
N
3
24V~
4
24V0
5
TN
6
T~
7
TO0
8
TN
9
TO1
10
RO3
11
IN3
12
RN
13
RN
14
IN0
15
RO0
16
IN1
17
RO1
18
IN2
19
RO2
AO0
26
24V~
27
GND
28
AO1
29
AO2
30
24V~
31
UI0
34
GND
35
UI1
36
/DA+
40
DB-
41
GND
42
UI2
37
GND
38
UI3
39
GND
32
AO3
33
WM1
20
WM2
21
24V~
22
/DA+
23
DB-
24
GND
25
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19
40 41 42
26 27 28 29 30 31 32 33
34 35 36 37 38 39
20 21 22
23 24 25
LEDs for RS-485 port 1 and port 0
The LEDs shown above indicate the data communication on the RS-485 port
in question.
Tx = send
Rx = receive
(x stands for the port number)
Ensure that the AC cables are separated from the signal wiring!
5.3.1
Schematic diagram of a PCD7.LRxx-P5 room controller in
an RS-485 bus with terminating resistors
An RS-485 bus must be terminated at both ends of its cable with terminating re-
sistors (see following figure). Since the PCD7.LRxx-P5 devices do not provide this
termination, it must be provided using other devices.
S-Bus cables must be connected in a line topology. Stubs are not allowed, and
both ends of the cable must be terminated with a resistor (approx. 120 Ω) between
the D and /D cables. The best signal quality is achieved through active bus termi-
nation, each with a resistance to +5 V and GND.
Devices that can do this on both sides of the S-Bus cable without much effort are:
►
All Saia PCD
®
CPUs
►
Termination boxes PCD7.T161 (230 VAC) or PCD7.T162 (24 V DC)
►
Third-party devices with this function are suitable for this purpose.