Connecting To The Remote Modem - Siemens 7SG11 Manual

If possible Data Carrier Detect (DCD) should be forced on, as this control line will be used by the Fibre-optic
converter.
Finally, these settings should be stored in the modem's memory for power on defaults.

4.2.17 Connecting to the Remote Modem

Once the remote modem has been configured correctly it should be possible to dial up the modem and make
connection to the relay. As the settings on the remote modem are fixed the local modem should negotiate with it
on connection choosing suitable matching settings. If it cannot do this, the local modem should be set with
settings equivalent to those of the remote modem as described above.
Laptop computer
Figure 4.2-1
Laptop computer
Figure 4.2-2
Control
System
Laptop computer
optional 12 VDC
power supply
Figure 4.2-3 Communication to Multiple Argus Relays from Control System and Laptop with Sigma 3
©2013 Siemens Protection Devices Limited
Sigma 4
(SG4-103)
Communication to Argus Relay using Sigma 4 (Local Connection)
Telephone
Network
Communication to Argus Relay using Sigma 4 and Modem
Sigma 3
(SG4-103)
and Fibre-optic Ring Network
7SG11 Argus Technical Reference
Tx
Rx
P300007 Communications.vsd / Sigma 4 remote
Tx
Sigma 4
(SG4-103)
Rx
P300007 Communications.vsd / Sigma 4 remote
Rx Tx
serial
optical
ring
Tx
Rx Tx Rx
P300007 Communications.vsd / Sigma 3
Rx
Tx
Rx
Tx
Rx Tx
Tx Rx
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