Installation And Operation; Installation With Direct Connection To A Computer; Installation With Connection To A Modem - Siemens COM32 Installation & Operation Manual

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Installation and Operation

COM32 INSTALLATION & OPERATION MANUAL

2.1 Installation with Direct Connection to a Computer

Since the COM32 device is configured as DCE (data communications equipment)
it may be connected directly to the serial port of a standard PC, which will be DTE
(data terminal equipment). As shown in Figure 2.1.1, the DB-23 connector on the
COM32 unit is connected directly (wires run straight through and do not cross) to
the DB-23 connector of the computer.
To make the connection between the COM32 and the RS-485 bus, use a shielded
twisted-pair cable. Make the RS-485 connections to the "Data +" and "Data -"
terminals of the COM32. Ensure that the polarity is correct.
When running WinPM software on a PC, in a direct connect mode, the RTS line of
the RS-232 will control the RS-285 data direction. The switch settings on the
COM32 for direct connection should be as follows:
SW-1: OFF (ignore carrier detect)
SW-2: ON (Automatic Flow Control)
Refer to Figure 2.1.1 for more information.
Figure 2.1.1 COM32 Direct Connection to a Computer

2.2 Installation with Connection to a Modem

Figure 2.2.1 shows connection of the COM32 with a modem. Since both the
COM32 unit and the modem are configured as DCE (data communications
equipment) the interface between the two must be done using a null modem
cable. A null modem cable swaps certain pins between the two ends.
N
OTE
When using a dial-up modem to communicate with 4000 or 9000-series meters, Siemens recommends
using the COM128 instead of the COM32.
The DB-25 connector on the COM32 converter is connected to the DB-25
connector of the modem using the null modem cable. A shielded twisted-pair
Installation and Operation
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