Instructions for use
SCU 835 / SEC 15
Note
If the remote station, such as
PLC
/
FACP
, requires other settings, these can be set via the configuration
wizard in the graphical user interface
GUI d-LISTconfig
(→ Operating manual
60T340
).
Information about d-LIST network with
RS485
bus:
Maximum cable length:
1.200 m
at
19.200 bd
, without amplifier or repeater
Wiring:
Twisted pair cable with
120 Ω
impedance, no star wiring of the bus
Termination:
Active
→
always
takes place at the communication master
Passive
→
set
jumper at
JP301
, termination with
120 Ω
, at the end of the
bus (last
SCU 835
)
No termination → all
jumpers at
JP301 open
Important note
An active resp. passive termination at
J301
is used if:
1. an external communication master is connected to the first sensor control unit
SCU 835
as shown in
PLC
,
FACP
).
2.
no
communication master is connected to the first sensor control unit
SCU 835
. In this case, the first
unit
must
be terminated as shown in figure
6.9
USB Interface
The
USB
interface can be used for direct connection to a
PC
for maintenance and analysis purposes as well as for
creating/modifying the unit configuration. A firmware update is generally
only
possible via this interface (→ 3.19).
The interface is factory set to
115200 Baud
and
cannot
be changed.
Page 58/112
LISTEC GmbH
60T328-02-LI-en / 29.01.2021
Fig. 117:
120 Ω
termination at
J301
passive termination
Fig. 116: Jumper at
J301
open
no termination
Fig. 115:
390 - 220 - 390 Ω
at
J301
active termination
Fig. 118:
USB
interface
Fig. 114:
RS485
bus termination (example with permanently active communication master)
