Siemens SINAUT ST7 System Manual page 213

Note
Any TIM with an RS-485 port can be used, in other words, all TIM 4 types and the
TIM 4R-IE. The TIM 3V-IE variants only have an RS-232 interface. If necessary, a
commercially available RS-232/RS-485 converter would need to be used.
Note
Do not forget to activate the terminating resistor for the RS-485 bus on the last connector
using the slider switch.
The dedicated line is connected over the LTOP 1 or LTOP 2 overvoltage protection module.
The figure shows various options for connecting a 1 x 2-wire, 1 x 4-wire or 2 x 2-wire end
point per MD2 modem. Depending on the type of end point, a setting must be made on the
modem at the 5-pin DIL switch accessible from above.
RS-485 operation of the MD2
If several MD2s are connected in parallel over the RS-485 port, remember the following
when making the settings for the modem and setting the parameters for the TIM:
1. The MD2 modem must be set to the "interface with RS-485" mode using the 10-pin DIL
2. The RS-485 interface must also be activated at the 4-pin DIL switch accessible from
3. The RS-485 interface of the TIM connected to the MD2 modem must also be activated at
4. When setting the parameters for the WAN access of the TIM connected to the MD2,
Station control system
System Manual, 07/2009, C79000-G8976-C178-07
switch.
below.
the 8-pin DIL switch accessible from above (applies to all TIM 4 types).
remember that a RTS-CTS delay ≥ 1 ms must be configured.
Figure 5-19 Setting parameters for the WAN access in the "Dedicated Line" tab
Note
If the MD2 is operated over its RS-485 port, no communication with the otherwise
incompatible MD100 modem is possible. These are only compatible when the RS-232
port of the MD2 is used.
Installing and putting a SINAUT modem into operation
5.5 MD2 dedicated line modem
213