Other Devices With Rs-232 Interface; Fe260 Function Expansion (Optionally With Modem) - Elster EK260 Operating Manual And Installation Instructions

5.5.4 Other devices with RS-232 interface

Connection diagram:

5.5.5 FE260 Function Expansion (optionally with modem)

! For this application the EK260 also needs the external power supp ly through the
FE260, i.e. the Uext+ and - terminals must be connected (see below). No data
transmission can take place during a power failure.
Connection diagram:
1
The connected device must switch the signal used to active before the start of the
communication and inactive again after the communication has terminated.
Elster GmbH
EK260
TD / T-
RS / T+
RD / R-
CS / R+
Ri
Gnd
EK260
TD / T-
RS / T+
RD / R-
CS / R+
Ri (open)
Gnd (open)
+
Uext
-
Volume Conversion Device EK260
Connected device
(RS-232)
→
RxD
→
DSR or CTS
←
TxD
←
DTR or RTS
Gnd
FE260
→
T-
→
T+
←
R-
←
R+
+
U
-
1
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